Brand, new sed that uses libc regex routines.
authorMark Whitley <markw@lineo.com>
Mon, 10 Jul 2000 22:55:51 +0000 (22:55 -0000)
committerMark Whitley <markw@lineo.com>
Mon, 10 Jul 2000 22:55:51 +0000 (22:55 -0000)
There is some common code used by both sed & grep that should be put into
utility.c as per Mat Kraai's suggestions/patch on the mailing list.
Specifically, a common regex_compile() and a regex_subst() function need to be
made.

editors/sed.c
sed.c

index d4b721e..329f5ae 100644 (file)
@@ -1,15 +1,8 @@
-/* vi: set sw=4 ts=4: */
 /*
- * Mini sed implementation for busybox
- *
+ * sed.c - very minimalist version of sed
  *
  * Copyright (C) 1999,2000 by Lineo, inc.
- * Written by Erik Andersen <andersen@lineo.com>, <andersee@debian.org>
- *
- * Modifications for addresses and append command have been
- * written by Marco Pantaleoni <panta@prosa.it>, <panta@elasticworld.org>
- * and are:
- * Copyright (C) 1999 Marco Pantaleoni.
+ * Written by Mark Whitley <markw@lineo.com>, <markw@enol.com>
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
  *
  */
 
-#include "internal.h"
-#include "regexp.h"
+/*
+       Supported features and commands in this version of sed:
+
+        - comments ('#')
+        - Address matching: num|/matchstr/[,num|/matchstr/|$]command
+        - Commands: p, d, s/match/replace/[g]
+        
+        (Note: Specifying an address (range) to match is *optional*; commands
+        default to the whole pattern space if no specific address match was
+        requested.)
+
+       Unsupported features:
+
+        - transliteration (y/source-chars/dest-chars/) (use 'tr')
+        - no support for characters other than the '/' character for regex matches
+        - no pattern space hold space storing / swapping (x, etc.)
+        - no labels / branching (: label, b, t, and friends)
+        - and lots, lots more.
+
+*/
+
 #include <stdio.h>
-#include <dirent.h>
+#include <stdlib.h> /* for realloc() */
+#include <unistd.h> /* for getopt() */
+#include <regex.h>
+#include <string.h> /* for strdup() */
 #include <errno.h>
-#include <fcntl.h>
-#include <signal.h>
-#include <time.h>
-#include <ctype.h>
+#include <ctype.h> /* for isspace() */
+#include "internal.h"
+
+
+/* externs */
+extern int optind; /* in unistd.h */
+extern char *optarg; /* ditto */
+
+/* options */
+static int be_quiet = 0;
+
+struct sed_cmd {
+
+       /* address storage */
+       int beg_line; /* 'sed 1p'   0 == no begining line, apply commands to all lines */
+       int end_line; /* 'sed 1,3p' 0 == no end line, use only beginning. -1 == $ */
+       regex_t *beg_match; /* sed -e '/match/cmd' */
+       regex_t *end_match; /* sed -e '/match/,/end_match/cmd' */
+
+       /* the command */
+       char cmd; /* p,d,s (add more at your leisure :-) */
+
+       /* substitution command specific fields */
+       regex_t *sub_match; /* sed -e 's/sub_match/replace/' */
+       char *replace; /* sed -e 's/sub_match/replace/' XXX: who will hold the \1 \2 \3s? */
+       unsigned int sub_g:1; /* sed -e 's/foo/bar/g' (global) */
+};
+
+/* globals */
+static struct sed_cmd *sed_cmds = NULL; /* growable arrary holding a sequence of sed cmds */
+static int ncmds = 0; /* number of sed commands */
+
+/*static char *cur_file = NULL;*/ /* file currently being processed XXX: do I need this? */
 
 static const char sed_usage[] =
-       "sed [-n] -e script [file...]\n"
+       "sed [-Vhnef] pattern [files...]\n"
 #ifndef BB_FEATURE_TRIVIAL_HELP
-       "\nAllowed sed scripts come in the following form:\n"
-       "\t'ADDR [!] COMMAND'\n\n"
-       "\twhere address ADDR can be:\n"
-       "\t  NUMBER    Match specified line number\n"
-       "\t  $         Match last line\n"
-       "\t  /REGEXP/  Match specified regexp\n"
-       "\t  (! inverts the meaning of the match)\n\n"
-       "\tand COMMAND can be:\n"
-       "\t  s/regexp/replacement/[igp]\n"
-       "\t     which attempt to match regexp against the pattern space\n"
-       "\t     and if successful replaces the matched portion with replacement.\n\n"
-       "\t  aTEXT\n"
-       "\t     which appends TEXT after the pattern space\n"
-       "Options:\n"
-       "-e\tadd the script to the commands to be executed\n"
-       "-n\tsuppress automatic printing of pattern space\n\n"
-#if defined BB_REGEXP
-       "This version of sed matches full regular expressions.\n";
-#else
-       "This version of sed matches strings (not full regular expressions).\n"
-#endif
+       "\n"
+       "-n\tsuppress automatic printing of pattern space\n"
+       "-e script\tadd the script to the commands to be executed\n"
+       "-f scriptfile\tadd the contents of script-file to the commands to be executed\n"
+       "-h\tdisplay this help message\n"
+       "-V\toutput version information and exit\n"
+       "\n"
+       "If no -e or -f is given, the first non-option argument is taken as the\n"
+       "sed script to interpret. All remaining arguments are names of input\n"
+       "files; if no input files are specified, then the standard input is read.\n"
 #endif
        ;
 
-/* Flags & variables */
+#if 0
+/* Nuke from here { */
 
-typedef enum { f_none, f_replace, f_append } sed_function;
 
-#define NO_LINE                -2
-#define LAST_LINE      -1
-static int addr_line = NO_LINE;
-static char *addr_pattern = NULL;
-static int negated = 0;
+/* get_line_from_file() - This function reads an entire line from a text file
+ *  * up to a newline. It returns a malloc'ed char * which must be stored and
+ *   * free'ed  by the caller. */
+extern char *get_line_from_file(FILE *file)
+{
+       static const int GROWBY = 80; /* how large we will grow strings by */
 
-#define SKIPSPACES(p)          do { while (isspace(*(p))) (p)++; } while (0)
+       int ch; 
+       int idx = 0;
+       char *linebuf = NULL;
+       int linebufsz = 0;
 
-#define BUFSIZE                1024
+       while (1) {
+               ch = fgetc(file);
+               if (ch == EOF)
+                       break;
+               /* grow the line buffer as necessary */
+               if (idx > linebufsz-2)
+                       linebuf = realloc(linebuf, linebufsz += GROWBY);
+               linebuf[idx++] = (char)ch;
+               if ((char)ch == '\n')
+                       break;
+       }
+
+       if (idx == 0)
+               return NULL;
+
+       linebuf[idx] = 0;
+       return linebuf;
+}
 
-static inline int at_last(FILE * fp)
+static void usage(const char *string)
 {
-       int res = 0;
+       printf("usage: %s\n", string);
+       exit(0);
+}
 
-       if (feof(fp))
-               return 1;
-       else {
-               int ch;
+/* } to here when we integrate this into busybox */
+#endif
+
+static void destroy_cmd_strs()
+{
+       if (sed_cmds == NULL)
+               return;
+
+       /* destroy all the elements in the array */
+       while (--ncmds >= 0) {
 
-               if ((ch = fgetc(fp)) == EOF)
-                       res++;
-               ungetc(ch, fp);
+               if (sed_cmds[ncmds].beg_match) {
+                       regfree(sed_cmds[ncmds].beg_match);
+                       free(sed_cmds[ncmds].beg_match);
+               }
+               if (sed_cmds[ncmds].end_match) {
+                       regfree(sed_cmds[ncmds].end_match);
+                       free(sed_cmds[ncmds].end_match);
+               }
+               if (sed_cmds[ncmds].sub_match) {
+                       regfree(sed_cmds[ncmds].sub_match);
+                       free(sed_cmds[ncmds].sub_match);
+               }
+               if (sed_cmds[ncmds].replace)
+                       free(sed_cmds[ncmds].replace);
        }
-       return res;
+
+       /* destroy the array */
+       free(sed_cmds);
+       sed_cmds = NULL;
+}
+
+static void exit_sed(int retcode, const char *message)
+{
+       destroy_cmd_strs();
+       if (message)
+               fputs(message, stderr);
+       exit(retcode);
 }
 
-static void do_sed_repl(FILE * fp, char *needle, char *newNeedle,
-                                               int ignoreCase, int printFlag, int quietFlag)
+/*
+ * trim_str - trims leading and trailing space from a string
+ * 
+ * Note: This returns a malloc'ed string so you must store and free it
+ * XXX: This should be in the utility.c file.
+ */
+static char *trim_str(const char *str)
+{
+       int i;
+       char *retstr = strdup(str);
+
+       /* trim leading whitespace */
+       memmove(retstr, &retstr[strspn(retstr, " \n\t\v")], strlen(retstr));
+
+       /* trim trailing whitespace */
+       i = strlen(retstr) - 1;
+       while (isspace(retstr[i]))
+               i--;
+       retstr[++i] = 0;
+
+       /* Aside: 
+        *
+        * you know, a strrspn() would really be nice cuz then we could say:
+        * 
+        * retstr[strlen(retstr) - strrspn(retstr, " \n\t\v") + 1] = 0;
+        */
+       
+       return retstr;
+}
+
+/*
+ * index_of_unescaped_slash - walks left to right through a string beginning
+ * at a specified index and returns the index of the next unescaped slash.
+ */
+static int index_of_next_unescaped_slash(int idx, const char *str)
+{
+       do {
+               idx++;
+               /* test if we've hit the end */
+               if (str[idx] == 0)
+                       return -1;
+       } while (str[idx] != '/' && str[idx - 1] != '\\');
+
+       return idx;
+}
+
+/*
+ * returns the index in the string just past where the address ends.
+ */
+static int get_address(const char *str, int *line, regex_t **regex)
 {
-       int foundOne = FALSE;
-       char haystack[BUFSIZE];
-       int line = 1, doit;
-
-       while (fgets(haystack, BUFSIZE - 1, fp)) {
-               doit = 0;
-               if (addr_pattern) {
-                       doit = !find_match(haystack, addr_pattern, FALSE);
-               } else if (addr_line == NO_LINE)
-                       doit = 1;
-               else if (addr_line == LAST_LINE) {
-                       if (at_last(fp))
-                               doit = 1;
-               } else {
-                       if (line == addr_line)
-                               doit = 1;
+       char *my_str = strdup(str);
+       int idx = 0;
+
+       if (isdigit(my_str[idx])) {
+               do {
+                       idx++;
+               } while (isdigit(my_str[idx]));
+               my_str[idx] = 0;
+               *line = atoi(my_str);
+               *regex = NULL;
+       }
+       else if (my_str[idx] == '$') {
+               *line = -1;
+               *regex = NULL;
+               idx++;
+       }
+       else if (my_str[idx] == '/') {
+               int ret;
+               idx = index_of_next_unescaped_slash(idx, my_str);
+               if (idx == -1) {
+                       free(my_str);
+                       exit_sed(1, "sed: unterminated match expression\n");
                }
-               if (negated)
-                       doit = 1 - doit;
-               if (doit) {
-                       foundOne =
-                               replace_match(haystack, needle, newNeedle, ignoreCase);
-
-                       if (foundOne == TRUE && printFlag == TRUE) {
-                               fprintf(stdout, haystack);
+               my_str[idx] = 0; /* shave off the trailing '/' */
+               my_str++; /* shave off the leading '/' */
+               *regex = (regex_t *)malloc(sizeof(regex_t));
+               if ((ret = regcomp(*regex, my_str, 0)) != 0) {
+                       /* error handling if regular expression couldn't be compiled */
+                       int errmsgsz = regerror(ret, *regex, NULL, 0);
+                       char *errmsg = malloc(errmsgsz);
+                       if (errmsg == NULL) {
+                               exit_sed(1, "sed: memory error\n");
                        }
+                       regerror(ret, *regex, errmsg, errmsgsz);
+                       fprintf(stderr, "sed: %s\n", errmsg);
+                       free(errmsg);
+                       exit_sed(1, NULL);
                }
+               my_str--; /* move my_str back so free() (below) won't barf */
+               idx++; /* advance idx one past the end of the /match/ */
+       }
+       else {
+               fprintf(stderr, "sed.c:get_address: no address found in string\n");
+               fprintf(stderr, "\t(you probably didn't check the string you passed me)\n");
+               idx = -1;
+       }
 
-               if (quietFlag == FALSE) {
-                       fprintf(stdout, haystack);
-               }
+       free(my_str);
+       return idx;
+}
 
-               line++;
+static void parse_cmd_str(struct sed_cmd *sed_cmd, const char *cmdstr)
+{
+       int idx = 0;
+
+       /* parse the command
+        * format is: [addr][,addr]cmd
+        *            |----||-----||-|
+        *            part1 part2  part3
+        */
+
+       /* first part (if present) is an address: either a number or a /regex/ */
+       if (isdigit(cmdstr[idx]) || cmdstr[idx] == '/')
+               idx = get_address(cmdstr, &sed_cmd->beg_line, &sed_cmd->beg_match);
+
+       /* second part (if present) will begin with a comma */
+       if (cmdstr[idx] == ',')
+               idx += get_address(&cmdstr[++idx], &sed_cmd->end_line, &sed_cmd->end_match);
+
+       /* last part (mandatory) will be a command */
+       if (cmdstr[idx] == '\0')
+               exit_sed(1, "sed: missing command\n");
+       if (!strchr("pds", cmdstr[idx])) /* <-- XXX add new commands here */
+               exit_sed(1, "sed: invalid command\n");
+       sed_cmd->cmd = cmdstr[idx];
+       /* special-case handling for 's' */
+       if (sed_cmd->cmd == 's') {
+               int oldidx;
+               /* format for substitution is:
+                *    s/match/replace/g
+                *    |               |
+                *    mandatory       optional
+                */
+
+               /* verify that we have an 's' followed by a 'slash' */
+               if (cmdstr[++idx] != '/')
+                       exit_sed(1, "sed: bad format in substitution expression\n");
+
+               /* get the substitution part */
+               idx += get_address(&cmdstr[idx], NULL, &sed_cmd->sub_match);
+
+               /* get the replacement part */
+               oldidx = idx;
+               idx = index_of_next_unescaped_slash(idx, cmdstr);
+               sed_cmd->replace = (char *)malloc(idx - oldidx + 1);
+               strncpy(sed_cmd->replace, &cmdstr[oldidx], idx - oldidx);
+               sed_cmd->replace[idx - oldidx] = 0;
+
+               /* store the 'g' if present */
+               if (cmdstr[++idx] == 'g')
+                       sed_cmd->sub_g = 1;
        }
 }
 
-static void do_sed_append(FILE * fp, char *appendline, int quietFlag)
+static void add_cmd_str(const char *cmdstr)
 {
-       char buffer[BUFSIZE];
-       int line = 1, doit;
-
-       while (fgets(buffer, BUFSIZE - 1, fp)) {
-               doit = 0;
-               if (addr_pattern) {
-                       doit = !find_match(buffer, addr_pattern, FALSE);
-               } else if (addr_line == NO_LINE)
-                       doit = 1;
-               else if (addr_line == LAST_LINE) {
-                       if (at_last(fp))
-                               doit = 1;
-               } else {
-                       if (line == addr_line)
-                               doit = 1;
-               }
-               if (negated)
-                       doit = 1 - doit;
-               if (quietFlag == FALSE) {
-                       fprintf(stdout, buffer);
-               }
-               if (doit) {
-                       fputs(appendline, stdout);
-                       fputc('\n', stdout);
-               }
+       char *my_cmdstr = trim_str(cmdstr);
 
-               line++;
+       /* if this is a comment, don't even bother */
+       if (my_cmdstr[0] == '#') {
+               free(my_cmdstr);
+               return;
        }
+
+       /* grow the array */
+       sed_cmds = realloc(sed_cmds, sizeof(struct sed_cmd) * (++ncmds));
+       /* zero new element */
+       memset(&sed_cmds[ncmds-1], 0, sizeof(struct sed_cmd));
+       /* load command string into new array element */
+       parse_cmd_str(&sed_cmds[ncmds-1], my_cmdstr);
 }
 
-extern int sed_main(int argc, char **argv)
+
+static void load_cmd_file(char *filename)
 {
-       FILE *fp;
-       char *needle = NULL, *newNeedle = NULL;
-       char *name;
-       char *cp;
-       int ignoreCase = FALSE;
-       int printFlag = FALSE;
-       int quietFlag = FALSE;
-       int stopNow;
-       char *line_s = NULL, saved;
-       char *appendline = NULL;
-       char *pos;
-       sed_function sed_f = f_none;
-
-       argc--;
-       argv++;
-       if (argc < 1) {
-               usage(sed_usage);
+       FILE *cmdfile;
+       char *line;
+
+       cmdfile = fopen(filename, "r");
+       if (cmdfile == NULL)
+               exit_sed(1, strerror(errno));
+
+       while ((line = get_line_from_file(cmdfile)) != NULL) {
+               line[strlen(line)-1] = 0; /* eat newline */
+               add_cmd_str(line);
+               free(line);
        }
+}
 
-       while (argc > 1) {
-               if (**argv != '-')
-                       usage(sed_usage);
-               argc--;
-               cp = *argv++;
-               stopNow = FALSE;
 
-               while (*++cp && stopNow == FALSE) {
-                       switch (*cp) {
-                       case 'n':
-                               quietFlag = TRUE;
-                               break;
-                       case 'e':
-                               if (*(cp + 1) == 0 && --argc < 0) {
-                                       usage(sed_usage);
-                               }
-                               if (*++cp != 's')
-                                       cp = *argv++;
-
-                               /* Read address if present */
-                               SKIPSPACES(cp);
-                               if (*cp == '$') {
-                                       addr_line = LAST_LINE;
-                                       cp++;
-                               } else {
-                                       if (isdigit(*cp)) {     /* LINE ADDRESS   */
-                                               line_s = cp;
-                                               while (isdigit(*cp))
-                                                       cp++;
-                                               if (cp > line_s) {
-                                                       /* numeric line */
-                                                       saved = *cp;
-                                                       *cp = '\0';
-                                                       addr_line = atoi(line_s);
-                                                       *cp = saved;
-                                               }
-                                       } else if (*cp == '/') {        /* PATTERN ADDRESS */
-                                               pos = addr_pattern = cp + 1;
-                                               pos = strchr(pos, '/');
-                                               if (!pos)
-                                                       usage(sed_usage);
-                                               *pos = '\0';
-                                               cp = pos + 1;
-                                       }
-                               }
+static int do_sed_command(const struct sed_cmd *sed_cmd, const char *line) 
+{
+       int altered = 0;
 
-                               SKIPSPACES(cp);
-                               if (*cp == '!') {
-                                       negated++;
-                                       cp++;
-                               }
+       switch (sed_cmd->cmd) {
 
-                               /* Read command */
+               case 'p':
+                       fputs(line, stdout);
+                       break;
 
-                               SKIPSPACES(cp);
-                               switch (*cp) {
-                               case 's':               /* REPLACE */
-                                       if (strlen(cp) <= 3 || *(cp + 1) != '/')
-                                               break;
-                                       sed_f = f_replace;
-
-                                       pos = needle = cp + 2;
-
-                                       for (;;) {
-                                               pos = strchr(pos, '/');
-                                               if (pos == NULL) {
-                                                       usage(sed_usage);
-                                               }
-                                               if (*(pos - 1) == '\\') {
-                                                       pos++;
-                                                       continue;
-                                               }
-                                               break;
+               case 'd':
+                       altered++;
+                       break;
+
+               case 's': /* oo, a fun one :-) */
+
+                       /* we only substitute if the substitution 'search' expression matches */
+                       if (regexec(sed_cmd->sub_match, line, 0, NULL, 0) == 0) {
+                               regmatch_t regmatch;
+                               int i;
+                               char *ptr = (char *)line;
+
+                               while (*ptr) {
+                                       /* if we can match the search string... */
+                                       if (regexec(sed_cmd->sub_match, ptr, 1, &regmatch, 0) == 0) {
+                                               /* print everything before the match, */
+                                               for (i = 0; i < regmatch.rm_so; i++)
+                                                       fputc(ptr[i], stdout);
+                                               /* then print the substitution in its place */
+                                               fputs(sed_cmd->replace, stdout);
+                                               /* then advance past the match */
+                                               ptr += regmatch.rm_eo;
+                                               /* and let the calling function know that something
+                                                * has been changed */
+                                               altered++;
+
+                                               /* if we're not doing this globally... */
+                                               if (!sed_cmd->sub_g)
+                                                       break;
                                        }
-                                       *pos = 0;
-                                       newNeedle = ++pos;
-                                       for (;;) {
-                                               pos = strchr(pos, '/');
-                                               if (pos == NULL) {
-                                                       usage(sed_usage);
-                                               }
-                                               if (*(pos - 1) == '\\') {
-                                                       pos++;
-                                                       continue;
-                                               }
+                                       /* if we COULD NOT match the search string (meaning we've gone past
+                                        * all previous instances), get out */
+                                       else
                                                break;
-                                       }
-                                       *pos = 0;
-                                       if (pos + 2 != 0) {
-                                               while (*++pos) {
-                                                       switch (*pos) {
-                                                       case 'i':
-                                                               ignoreCase = TRUE;
-                                                               break;
-                                                       case 'p':
-                                                               printFlag = TRUE;
-                                                               break;
-                                                       case 'g':
-                                                               break;
-                                                       default:
-                                                               usage(sed_usage);
-                                                       }
-                                               }
-                                       }
-                                       cp = pos;
-                                       /* fprintf(stderr, "replace '%s' with '%s'\n", needle, newNeedle); */
-                                       break;
+                               }
 
-                               case 'a':               /* APPEND */
-                                       if (strlen(cp) < 2)
-                                               break;
-                                       sed_f = f_append;
-                                       appendline = ++cp;
-                                       /* fprintf(stderr, "append '%s'\n", appendline); */
-                                       break;
+                               /* is there anything left to print? */
+                               if (*ptr) 
+                                       fputs(ptr, stdout);
+                       }
+
+                       break;
+       }
+
+       return altered;
+}
+
+static void process_file(FILE *file)
+{
+       char *line = NULL;
+       static int linenum = 0; /* GNU sed does not restart counting lines at EOF */
+       unsigned int still_in_range = 0;
+       int line_altered;
+       int i;
+
+       /* go through every line in the file */
+       while ((line = get_line_from_file(file)) != NULL) {
+
+               linenum++;
+               line_altered = 0;
+
+               /* for every line, go through all the commands */
+               for (i = 0; i < ncmds; i++) {
+
+                       /* are we acting on a range of matched lines? */
+                       if (sed_cmds[i].beg_match && sed_cmds[i].end_match) {
+                               if (still_in_range || regexec(sed_cmds[i].beg_match, line, 0, NULL, 0) == 0) {
+                                       line_altered += do_sed_command(&sed_cmds[i], line);
+                                       still_in_range = 1; 
+                                       if (regexec(sed_cmds[i].end_match, line, 0, NULL, 0) == 0)
+                                               still_in_range = 0;
                                }
+                       }
 
-                               stopNow = TRUE;
-                               break;
+                       /* are we trying to match a single line? */
+                       else if (sed_cmds[i].beg_match) {
+                               if (regexec(sed_cmds[i].beg_match, line, 0, NULL, 0) == 0)
+                                       line_altered += do_sed_command(&sed_cmds[i], line);
+                       }
 
-                       default:
-                               usage(sed_usage);
+                       /* are we acting on a range of line numbers? */
+                       else if (sed_cmds[i].beg_line > 0 && sed_cmds[i].end_line > 0) {
+                               if (linenum >= sed_cmds[i].beg_line && linenum <= sed_cmds[i].end_line)
+                                       line_altered += do_sed_command(&sed_cmds[i], line);
                        }
-               }
-    }
 
-       if (argc == 0) {
-               switch (sed_f) {
-               case f_none:
-                       break;
-               case f_replace:
-                       do_sed_repl(stdin, needle, newNeedle, ignoreCase, printFlag,
-                                               quietFlag);
-                       break;
-               case f_append:
-                       do_sed_append(stdin, appendline, quietFlag);
-                       break;
-               }
-       } else {
-               while (argc-- > 0) {
-                       name = *argv++;
-
-                       fp = fopen(name, "r");
-                       if (fp == NULL) {
-                               perror(name);
-                               continue;
+                       /* are we acting on a specified line number */
+                       else if (sed_cmds[i].beg_line > 0) {
+                               if (linenum == sed_cmds[i].beg_line)
+                                       line_altered += do_sed_command(&sed_cmds[i], line);
                        }
 
-                       switch (sed_f) {
-                       case f_none:
+                       /* not acting on matches or line numbers. act on every line */
+                       else 
+                               line_altered += do_sed_command(&sed_cmds[i], line);
+
+               }
+
+               /* we will print the line unless we were told to be quiet or if the
+                * line was altered (via a 'd'elete or 's'ubstitution) */
+               if (!be_quiet && !line_altered)
+                       fputs(line, stdout);
+
+               free(line);
+       }
+}
+
+extern int sed_main(int argc, char **argv)
+{
+       int opt;
+
+    /* do special-case option parsing */
+       if (argv[1] && (strcmp(argv[1], "--help") == 0))
+               usage(sed_usage);
+
+       /* do normal option parsing */
+       while ((opt = getopt(argc, argv, "Vhne:f:")) > 0) {
+               switch (opt) {
+                       case 'V':
+                               printf("Print Busybox version here\n");
+                               exit(0);
                                break;
-                       case f_replace:
-                               do_sed_repl(fp, needle, newNeedle, ignoreCase, printFlag,
-                                                       quietFlag);
+                       case 'h':
+                               usage(sed_usage);
                                break;
-                       case f_append:
-                               do_sed_append(fp, appendline, quietFlag);
+                       case 'n':
+                               be_quiet++;
                                break;
-                       }
+                       case 'e':
+                               add_cmd_str(optarg);
+                               break;
+                       case 'f': 
+                               load_cmd_file(optarg);
+                               break;
+               }
+       }
+
+       /* if we didn't get a pattern from a -e and no command file was specified,
+        * argv[optind] should be the pattern. no pattern, no worky */
+       if (ncmds == 0) {
+               if (argv[optind] == NULL)
+                       usage(sed_usage);
+               else {
+                       add_cmd_str(argv[optind]);
+                       optind++;
+               }
+       }
 
-                       if (ferror(fp))
-                               perror(name);
 
-                       fclose(fp);
+       /* argv[(optind)..(argc-1)] should be names of file to process. If no
+        * files were specified or '-' was specified, take input from stdin.
+        * Otherwise, we process all the files specified. */
+       if (argv[optind] == NULL || (strcmp(argv[optind], "-") == 0)) {
+               process_file(stdin);
+       }
+       else {
+               int i;
+               FILE *file;
+               for (i = optind; i < argc; i++) {
+                       file = fopen(argv[i], "r");
+                       if (file == NULL) {
+                               fprintf(stderr, "sed: %s: %s\n", argv[i], strerror(errno));
+                       } else {
+                               process_file(file);
+                               fclose(file);
+                       }
                }
        }
-       return(TRUE);
-}
+       
+       exit_sed(0, NULL);
 
+       /* not reached */
+       return 0;
+}
 
-/* END CODE */
+#ifdef TEST_SED
+int main(int argc, char **argv)
+{
+       return sed_main(argc, argv);
+}
+#endif
diff --git a/sed.c b/sed.c
index d4b721e..329f5ae 100644 (file)
--- a/sed.c
+++ b/sed.c
@@ -1,15 +1,8 @@
-/* vi: set sw=4 ts=4: */
 /*
- * Mini sed implementation for busybox
- *
+ * sed.c - very minimalist version of sed
  *
  * Copyright (C) 1999,2000 by Lineo, inc.
- * Written by Erik Andersen <andersen@lineo.com>, <andersee@debian.org>
- *
- * Modifications for addresses and append command have been
- * written by Marco Pantaleoni <panta@prosa.it>, <panta@elasticworld.org>
- * and are:
- * Copyright (C) 1999 Marco Pantaleoni.
+ * Written by Mark Whitley <markw@lineo.com>, <markw@enol.com>
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
  *
  */
 
-#include "internal.h"
-#include "regexp.h"
+/*
+       Supported features and commands in this version of sed:
+
+        - comments ('#')
+        - Address matching: num|/matchstr/[,num|/matchstr/|$]command
+        - Commands: p, d, s/match/replace/[g]
+        
+        (Note: Specifying an address (range) to match is *optional*; commands
+        default to the whole pattern space if no specific address match was
+        requested.)
+
+       Unsupported features:
+
+        - transliteration (y/source-chars/dest-chars/) (use 'tr')
+        - no support for characters other than the '/' character for regex matches
+        - no pattern space hold space storing / swapping (x, etc.)
+        - no labels / branching (: label, b, t, and friends)
+        - and lots, lots more.
+
+*/
+
 #include <stdio.h>
-#include <dirent.h>
+#include <stdlib.h> /* for realloc() */
+#include <unistd.h> /* for getopt() */
+#include <regex.h>
+#include <string.h> /* for strdup() */
 #include <errno.h>
-#include <fcntl.h>
-#include <signal.h>
-#include <time.h>
-#include <ctype.h>
+#include <ctype.h> /* for isspace() */
+#include "internal.h"
+
+
+/* externs */
+extern int optind; /* in unistd.h */
+extern char *optarg; /* ditto */
+
+/* options */
+static int be_quiet = 0;
+
+struct sed_cmd {
+
+       /* address storage */
+       int beg_line; /* 'sed 1p'   0 == no begining line, apply commands to all lines */
+       int end_line; /* 'sed 1,3p' 0 == no end line, use only beginning. -1 == $ */
+       regex_t *beg_match; /* sed -e '/match/cmd' */
+       regex_t *end_match; /* sed -e '/match/,/end_match/cmd' */
+
+       /* the command */
+       char cmd; /* p,d,s (add more at your leisure :-) */
+
+       /* substitution command specific fields */
+       regex_t *sub_match; /* sed -e 's/sub_match/replace/' */
+       char *replace; /* sed -e 's/sub_match/replace/' XXX: who will hold the \1 \2 \3s? */
+       unsigned int sub_g:1; /* sed -e 's/foo/bar/g' (global) */
+};
+
+/* globals */
+static struct sed_cmd *sed_cmds = NULL; /* growable arrary holding a sequence of sed cmds */
+static int ncmds = 0; /* number of sed commands */
+
+/*static char *cur_file = NULL;*/ /* file currently being processed XXX: do I need this? */
 
 static const char sed_usage[] =
-       "sed [-n] -e script [file...]\n"
+       "sed [-Vhnef] pattern [files...]\n"
 #ifndef BB_FEATURE_TRIVIAL_HELP
-       "\nAllowed sed scripts come in the following form:\n"
-       "\t'ADDR [!] COMMAND'\n\n"
-       "\twhere address ADDR can be:\n"
-       "\t  NUMBER    Match specified line number\n"
-       "\t  $         Match last line\n"
-       "\t  /REGEXP/  Match specified regexp\n"
-       "\t  (! inverts the meaning of the match)\n\n"
-       "\tand COMMAND can be:\n"
-       "\t  s/regexp/replacement/[igp]\n"
-       "\t     which attempt to match regexp against the pattern space\n"
-       "\t     and if successful replaces the matched portion with replacement.\n\n"
-       "\t  aTEXT\n"
-       "\t     which appends TEXT after the pattern space\n"
-       "Options:\n"
-       "-e\tadd the script to the commands to be executed\n"
-       "-n\tsuppress automatic printing of pattern space\n\n"
-#if defined BB_REGEXP
-       "This version of sed matches full regular expressions.\n";
-#else
-       "This version of sed matches strings (not full regular expressions).\n"
-#endif
+       "\n"
+       "-n\tsuppress automatic printing of pattern space\n"
+       "-e script\tadd the script to the commands to be executed\n"
+       "-f scriptfile\tadd the contents of script-file to the commands to be executed\n"
+       "-h\tdisplay this help message\n"
+       "-V\toutput version information and exit\n"
+       "\n"
+       "If no -e or -f is given, the first non-option argument is taken as the\n"
+       "sed script to interpret. All remaining arguments are names of input\n"
+       "files; if no input files are specified, then the standard input is read.\n"
 #endif
        ;
 
-/* Flags & variables */
+#if 0
+/* Nuke from here { */
 
-typedef enum { f_none, f_replace, f_append } sed_function;
 
-#define NO_LINE                -2
-#define LAST_LINE      -1
-static int addr_line = NO_LINE;
-static char *addr_pattern = NULL;
-static int negated = 0;
+/* get_line_from_file() - This function reads an entire line from a text file
+ *  * up to a newline. It returns a malloc'ed char * which must be stored and
+ *   * free'ed  by the caller. */
+extern char *get_line_from_file(FILE *file)
+{
+       static const int GROWBY = 80; /* how large we will grow strings by */
 
-#define SKIPSPACES(p)          do { while (isspace(*(p))) (p)++; } while (0)
+       int ch; 
+       int idx = 0;
+       char *linebuf = NULL;
+       int linebufsz = 0;
 
-#define BUFSIZE                1024
+       while (1) {
+               ch = fgetc(file);
+               if (ch == EOF)
+                       break;
+               /* grow the line buffer as necessary */
+               if (idx > linebufsz-2)
+                       linebuf = realloc(linebuf, linebufsz += GROWBY);
+               linebuf[idx++] = (char)ch;
+               if ((char)ch == '\n')
+                       break;
+       }
+
+       if (idx == 0)
+               return NULL;
+
+       linebuf[idx] = 0;
+       return linebuf;
+}
 
-static inline int at_last(FILE * fp)
+static void usage(const char *string)
 {
-       int res = 0;
+       printf("usage: %s\n", string);
+       exit(0);
+}
 
-       if (feof(fp))
-               return 1;
-       else {
-               int ch;
+/* } to here when we integrate this into busybox */
+#endif
+
+static void destroy_cmd_strs()
+{
+       if (sed_cmds == NULL)
+               return;
+
+       /* destroy all the elements in the array */
+       while (--ncmds >= 0) {
 
-               if ((ch = fgetc(fp)) == EOF)
-                       res++;
-               ungetc(ch, fp);
+               if (sed_cmds[ncmds].beg_match) {
+                       regfree(sed_cmds[ncmds].beg_match);
+                       free(sed_cmds[ncmds].beg_match);
+               }
+               if (sed_cmds[ncmds].end_match) {
+                       regfree(sed_cmds[ncmds].end_match);
+                       free(sed_cmds[ncmds].end_match);
+               }
+               if (sed_cmds[ncmds].sub_match) {
+                       regfree(sed_cmds[ncmds].sub_match);
+                       free(sed_cmds[ncmds].sub_match);
+               }
+               if (sed_cmds[ncmds].replace)
+                       free(sed_cmds[ncmds].replace);
        }
-       return res;
+
+       /* destroy the array */
+       free(sed_cmds);
+       sed_cmds = NULL;
+}
+
+static void exit_sed(int retcode, const char *message)
+{
+       destroy_cmd_strs();
+       if (message)
+               fputs(message, stderr);
+       exit(retcode);
 }
 
-static void do_sed_repl(FILE * fp, char *needle, char *newNeedle,
-                                               int ignoreCase, int printFlag, int quietFlag)
+/*
+ * trim_str - trims leading and trailing space from a string
+ * 
+ * Note: This returns a malloc'ed string so you must store and free it
+ * XXX: This should be in the utility.c file.
+ */
+static char *trim_str(const char *str)
+{
+       int i;
+       char *retstr = strdup(str);
+
+       /* trim leading whitespace */
+       memmove(retstr, &retstr[strspn(retstr, " \n\t\v")], strlen(retstr));
+
+       /* trim trailing whitespace */
+       i = strlen(retstr) - 1;
+       while (isspace(retstr[i]))
+               i--;
+       retstr[++i] = 0;
+
+       /* Aside: 
+        *
+        * you know, a strrspn() would really be nice cuz then we could say:
+        * 
+        * retstr[strlen(retstr) - strrspn(retstr, " \n\t\v") + 1] = 0;
+        */
+       
+       return retstr;
+}
+
+/*
+ * index_of_unescaped_slash - walks left to right through a string beginning
+ * at a specified index and returns the index of the next unescaped slash.
+ */
+static int index_of_next_unescaped_slash(int idx, const char *str)
+{
+       do {
+               idx++;
+               /* test if we've hit the end */
+               if (str[idx] == 0)
+                       return -1;
+       } while (str[idx] != '/' && str[idx - 1] != '\\');
+
+       return idx;
+}
+
+/*
+ * returns the index in the string just past where the address ends.
+ */
+static int get_address(const char *str, int *line, regex_t **regex)
 {
-       int foundOne = FALSE;
-       char haystack[BUFSIZE];
-       int line = 1, doit;
-
-       while (fgets(haystack, BUFSIZE - 1, fp)) {
-               doit = 0;
-               if (addr_pattern) {
-                       doit = !find_match(haystack, addr_pattern, FALSE);
-               } else if (addr_line == NO_LINE)
-                       doit = 1;
-               else if (addr_line == LAST_LINE) {
-                       if (at_last(fp))
-                               doit = 1;
-               } else {
-                       if (line == addr_line)
-                               doit = 1;
+       char *my_str = strdup(str);
+       int idx = 0;
+
+       if (isdigit(my_str[idx])) {
+               do {
+                       idx++;
+               } while (isdigit(my_str[idx]));
+               my_str[idx] = 0;
+               *line = atoi(my_str);
+               *regex = NULL;
+       }
+       else if (my_str[idx] == '$') {
+               *line = -1;
+               *regex = NULL;
+               idx++;
+       }
+       else if (my_str[idx] == '/') {
+               int ret;
+               idx = index_of_next_unescaped_slash(idx, my_str);
+               if (idx == -1) {
+                       free(my_str);
+                       exit_sed(1, "sed: unterminated match expression\n");
                }
-               if (negated)
-                       doit = 1 - doit;
-               if (doit) {
-                       foundOne =
-                               replace_match(haystack, needle, newNeedle, ignoreCase);
-
-                       if (foundOne == TRUE && printFlag == TRUE) {
-                               fprintf(stdout, haystack);
+               my_str[idx] = 0; /* shave off the trailing '/' */
+               my_str++; /* shave off the leading '/' */
+               *regex = (regex_t *)malloc(sizeof(regex_t));
+               if ((ret = regcomp(*regex, my_str, 0)) != 0) {
+                       /* error handling if regular expression couldn't be compiled */
+                       int errmsgsz = regerror(ret, *regex, NULL, 0);
+                       char *errmsg = malloc(errmsgsz);
+                       if (errmsg == NULL) {
+                               exit_sed(1, "sed: memory error\n");
                        }
+                       regerror(ret, *regex, errmsg, errmsgsz);
+                       fprintf(stderr, "sed: %s\n", errmsg);
+                       free(errmsg);
+                       exit_sed(1, NULL);
                }
+               my_str--; /* move my_str back so free() (below) won't barf */
+               idx++; /* advance idx one past the end of the /match/ */
+       }
+       else {
+               fprintf(stderr, "sed.c:get_address: no address found in string\n");
+               fprintf(stderr, "\t(you probably didn't check the string you passed me)\n");
+               idx = -1;
+       }
 
-               if (quietFlag == FALSE) {
-                       fprintf(stdout, haystack);
-               }
+       free(my_str);
+       return idx;
+}
 
-               line++;
+static void parse_cmd_str(struct sed_cmd *sed_cmd, const char *cmdstr)
+{
+       int idx = 0;
+
+       /* parse the command
+        * format is: [addr][,addr]cmd
+        *            |----||-----||-|
+        *            part1 part2  part3
+        */
+
+       /* first part (if present) is an address: either a number or a /regex/ */
+       if (isdigit(cmdstr[idx]) || cmdstr[idx] == '/')
+               idx = get_address(cmdstr, &sed_cmd->beg_line, &sed_cmd->beg_match);
+
+       /* second part (if present) will begin with a comma */
+       if (cmdstr[idx] == ',')
+               idx += get_address(&cmdstr[++idx], &sed_cmd->end_line, &sed_cmd->end_match);
+
+       /* last part (mandatory) will be a command */
+       if (cmdstr[idx] == '\0')
+               exit_sed(1, "sed: missing command\n");
+       if (!strchr("pds", cmdstr[idx])) /* <-- XXX add new commands here */
+               exit_sed(1, "sed: invalid command\n");
+       sed_cmd->cmd = cmdstr[idx];
+       /* special-case handling for 's' */
+       if (sed_cmd->cmd == 's') {
+               int oldidx;
+               /* format for substitution is:
+                *    s/match/replace/g
+                *    |               |
+                *    mandatory       optional
+                */
+
+               /* verify that we have an 's' followed by a 'slash' */
+               if (cmdstr[++idx] != '/')
+                       exit_sed(1, "sed: bad format in substitution expression\n");
+
+               /* get the substitution part */
+               idx += get_address(&cmdstr[idx], NULL, &sed_cmd->sub_match);
+
+               /* get the replacement part */
+               oldidx = idx;
+               idx = index_of_next_unescaped_slash(idx, cmdstr);
+               sed_cmd->replace = (char *)malloc(idx - oldidx + 1);
+               strncpy(sed_cmd->replace, &cmdstr[oldidx], idx - oldidx);
+               sed_cmd->replace[idx - oldidx] = 0;
+
+               /* store the 'g' if present */
+               if (cmdstr[++idx] == 'g')
+                       sed_cmd->sub_g = 1;
        }
 }
 
-static void do_sed_append(FILE * fp, char *appendline, int quietFlag)
+static void add_cmd_str(const char *cmdstr)
 {
-       char buffer[BUFSIZE];
-       int line = 1, doit;
-
-       while (fgets(buffer, BUFSIZE - 1, fp)) {
-               doit = 0;
-               if (addr_pattern) {
-                       doit = !find_match(buffer, addr_pattern, FALSE);
-               } else if (addr_line == NO_LINE)
-                       doit = 1;
-               else if (addr_line == LAST_LINE) {
-                       if (at_last(fp))
-                               doit = 1;
-               } else {
-                       if (line == addr_line)
-                               doit = 1;
-               }
-               if (negated)
-                       doit = 1 - doit;
-               if (quietFlag == FALSE) {
-                       fprintf(stdout, buffer);
-               }
-               if (doit) {
-                       fputs(appendline, stdout);
-                       fputc('\n', stdout);
-               }
+       char *my_cmdstr = trim_str(cmdstr);
 
-               line++;
+       /* if this is a comment, don't even bother */
+       if (my_cmdstr[0] == '#') {
+               free(my_cmdstr);
+               return;
        }
+
+       /* grow the array */
+       sed_cmds = realloc(sed_cmds, sizeof(struct sed_cmd) * (++ncmds));
+       /* zero new element */
+       memset(&sed_cmds[ncmds-1], 0, sizeof(struct sed_cmd));
+       /* load command string into new array element */
+       parse_cmd_str(&sed_cmds[ncmds-1], my_cmdstr);
 }
 
-extern int sed_main(int argc, char **argv)
+
+static void load_cmd_file(char *filename)
 {
-       FILE *fp;
-       char *needle = NULL, *newNeedle = NULL;
-       char *name;
-       char *cp;
-       int ignoreCase = FALSE;
-       int printFlag = FALSE;
-       int quietFlag = FALSE;
-       int stopNow;
-       char *line_s = NULL, saved;
-       char *appendline = NULL;
-       char *pos;
-       sed_function sed_f = f_none;
-
-       argc--;
-       argv++;
-       if (argc < 1) {
-               usage(sed_usage);
+       FILE *cmdfile;
+       char *line;
+
+       cmdfile = fopen(filename, "r");
+       if (cmdfile == NULL)
+               exit_sed(1, strerror(errno));
+
+       while ((line = get_line_from_file(cmdfile)) != NULL) {
+               line[strlen(line)-1] = 0; /* eat newline */
+               add_cmd_str(line);
+               free(line);
        }
+}
 
-       while (argc > 1) {
-               if (**argv != '-')
-                       usage(sed_usage);
-               argc--;
-               cp = *argv++;
-               stopNow = FALSE;
 
-               while (*++cp && stopNow == FALSE) {
-                       switch (*cp) {
-                       case 'n':
-                               quietFlag = TRUE;
-                               break;
-                       case 'e':
-                               if (*(cp + 1) == 0 && --argc < 0) {
-                                       usage(sed_usage);
-                               }
-                               if (*++cp != 's')
-                                       cp = *argv++;
-
-                               /* Read address if present */
-                               SKIPSPACES(cp);
-                               if (*cp == '$') {
-                                       addr_line = LAST_LINE;
-                                       cp++;
-                               } else {
-                                       if (isdigit(*cp)) {     /* LINE ADDRESS   */
-                                               line_s = cp;
-                                               while (isdigit(*cp))
-                                                       cp++;
-                                               if (cp > line_s) {
-                                                       /* numeric line */
-                                                       saved = *cp;
-                                                       *cp = '\0';
-                                                       addr_line = atoi(line_s);
-                                                       *cp = saved;
-                                               }
-                                       } else if (*cp == '/') {        /* PATTERN ADDRESS */
-                                               pos = addr_pattern = cp + 1;
-                                               pos = strchr(pos, '/');
-                                               if (!pos)
-                                                       usage(sed_usage);
-                                               *pos = '\0';
-                                               cp = pos + 1;
-                                       }
-                               }
+static int do_sed_command(const struct sed_cmd *sed_cmd, const char *line) 
+{
+       int altered = 0;
 
-                               SKIPSPACES(cp);
-                               if (*cp == '!') {
-                                       negated++;
-                                       cp++;
-                               }
+       switch (sed_cmd->cmd) {
 
-                               /* Read command */
+               case 'p':
+                       fputs(line, stdout);
+                       break;
 
-                               SKIPSPACES(cp);
-                               switch (*cp) {
-                               case 's':               /* REPLACE */
-                                       if (strlen(cp) <= 3 || *(cp + 1) != '/')
-                                               break;
-                                       sed_f = f_replace;
-
-                                       pos = needle = cp + 2;
-
-                                       for (;;) {
-                                               pos = strchr(pos, '/');
-                                               if (pos == NULL) {
-                                                       usage(sed_usage);
-                                               }
-                                               if (*(pos - 1) == '\\') {
-                                                       pos++;
-                                                       continue;
-                                               }
-                                               break;
+               case 'd':
+                       altered++;
+                       break;
+
+               case 's': /* oo, a fun one :-) */
+
+                       /* we only substitute if the substitution 'search' expression matches */
+                       if (regexec(sed_cmd->sub_match, line, 0, NULL, 0) == 0) {
+                               regmatch_t regmatch;
+                               int i;
+                               char *ptr = (char *)line;
+
+                               while (*ptr) {
+                                       /* if we can match the search string... */
+                                       if (regexec(sed_cmd->sub_match, ptr, 1, &regmatch, 0) == 0) {
+                                               /* print everything before the match, */
+                                               for (i = 0; i < regmatch.rm_so; i++)
+                                                       fputc(ptr[i], stdout);
+                                               /* then print the substitution in its place */
+                                               fputs(sed_cmd->replace, stdout);
+                                               /* then advance past the match */
+                                               ptr += regmatch.rm_eo;
+                                               /* and let the calling function know that something
+                                                * has been changed */
+                                               altered++;
+
+                                               /* if we're not doing this globally... */
+                                               if (!sed_cmd->sub_g)
+                                                       break;
                                        }
-                                       *pos = 0;
-                                       newNeedle = ++pos;
-                                       for (;;) {
-                                               pos = strchr(pos, '/');
-                                               if (pos == NULL) {
-                                                       usage(sed_usage);
-                                               }
-                                               if (*(pos - 1) == '\\') {
-                                                       pos++;
-                                                       continue;
-                                               }
+                                       /* if we COULD NOT match the search string (meaning we've gone past
+                                        * all previous instances), get out */
+                                       else
                                                break;
-                                       }
-                                       *pos = 0;
-                                       if (pos + 2 != 0) {
-                                               while (*++pos) {
-                                                       switch (*pos) {
-                                                       case 'i':
-                                                               ignoreCase = TRUE;
-                                                               break;
-                                                       case 'p':
-                                                               printFlag = TRUE;
-                                                               break;
-                                                       case 'g':
-                                                               break;
-                                                       default:
-                                                               usage(sed_usage);
-                                                       }
-                                               }
-                                       }
-                                       cp = pos;
-                                       /* fprintf(stderr, "replace '%s' with '%s'\n", needle, newNeedle); */
-                                       break;
+                               }
 
-                               case 'a':               /* APPEND */
-                                       if (strlen(cp) < 2)
-                                               break;
-                                       sed_f = f_append;
-                                       appendline = ++cp;
-                                       /* fprintf(stderr, "append '%s'\n", appendline); */
-                                       break;
+                               /* is there anything left to print? */
+                               if (*ptr) 
+                                       fputs(ptr, stdout);
+                       }
+
+                       break;
+       }
+
+       return altered;
+}
+
+static void process_file(FILE *file)
+{
+       char *line = NULL;
+       static int linenum = 0; /* GNU sed does not restart counting lines at EOF */
+       unsigned int still_in_range = 0;
+       int line_altered;
+       int i;
+
+       /* go through every line in the file */
+       while ((line = get_line_from_file(file)) != NULL) {
+
+               linenum++;
+               line_altered = 0;
+
+               /* for every line, go through all the commands */
+               for (i = 0; i < ncmds; i++) {
+
+                       /* are we acting on a range of matched lines? */
+                       if (sed_cmds[i].beg_match && sed_cmds[i].end_match) {
+                               if (still_in_range || regexec(sed_cmds[i].beg_match, line, 0, NULL, 0) == 0) {
+                                       line_altered += do_sed_command(&sed_cmds[i], line);
+                                       still_in_range = 1; 
+                                       if (regexec(sed_cmds[i].end_match, line, 0, NULL, 0) == 0)
+                                               still_in_range = 0;
                                }
+                       }
 
-                               stopNow = TRUE;
-                               break;
+                       /* are we trying to match a single line? */
+                       else if (sed_cmds[i].beg_match) {
+                               if (regexec(sed_cmds[i].beg_match, line, 0, NULL, 0) == 0)
+                                       line_altered += do_sed_command(&sed_cmds[i], line);
+                       }
 
-                       default:
-                               usage(sed_usage);
+                       /* are we acting on a range of line numbers? */
+                       else if (sed_cmds[i].beg_line > 0 && sed_cmds[i].end_line > 0) {
+                               if (linenum >= sed_cmds[i].beg_line && linenum <= sed_cmds[i].end_line)
+                                       line_altered += do_sed_command(&sed_cmds[i], line);
                        }
-               }
-    }
 
-       if (argc == 0) {
-               switch (sed_f) {
-               case f_none:
-                       break;
-               case f_replace:
-                       do_sed_repl(stdin, needle, newNeedle, ignoreCase, printFlag,
-                                               quietFlag);
-                       break;
-               case f_append:
-                       do_sed_append(stdin, appendline, quietFlag);
-                       break;
-               }
-       } else {
-               while (argc-- > 0) {
-                       name = *argv++;
-
-                       fp = fopen(name, "r");
-                       if (fp == NULL) {
-                               perror(name);
-                               continue;
+                       /* are we acting on a specified line number */
+                       else if (sed_cmds[i].beg_line > 0) {
+                               if (linenum == sed_cmds[i].beg_line)
+                                       line_altered += do_sed_command(&sed_cmds[i], line);
                        }
 
-                       switch (sed_f) {
-                       case f_none:
+                       /* not acting on matches or line numbers. act on every line */
+                       else 
+                               line_altered += do_sed_command(&sed_cmds[i], line);
+
+               }
+
+               /* we will print the line unless we were told to be quiet or if the
+                * line was altered (via a 'd'elete or 's'ubstitution) */
+               if (!be_quiet && !line_altered)
+                       fputs(line, stdout);
+
+               free(line);
+       }
+}
+
+extern int sed_main(int argc, char **argv)
+{
+       int opt;
+
+    /* do special-case option parsing */
+       if (argv[1] && (strcmp(argv[1], "--help") == 0))
+               usage(sed_usage);
+
+       /* do normal option parsing */
+       while ((opt = getopt(argc, argv, "Vhne:f:")) > 0) {
+               switch (opt) {
+                       case 'V':
+                               printf("Print Busybox version here\n");
+                               exit(0);
                                break;
-                       case f_replace:
-                               do_sed_repl(fp, needle, newNeedle, ignoreCase, printFlag,
-                                                       quietFlag);
+                       case 'h':
+                               usage(sed_usage);
                                break;
-                       case f_append:
-                               do_sed_append(fp, appendline, quietFlag);
+                       case 'n':
+                               be_quiet++;
                                break;
-                       }
+                       case 'e':
+                               add_cmd_str(optarg);
+                               break;
+                       case 'f': 
+                               load_cmd_file(optarg);
+                               break;
+               }
+       }
+
+       /* if we didn't get a pattern from a -e and no command file was specified,
+        * argv[optind] should be the pattern. no pattern, no worky */
+       if (ncmds == 0) {
+               if (argv[optind] == NULL)
+                       usage(sed_usage);
+               else {
+                       add_cmd_str(argv[optind]);
+                       optind++;
+               }
+       }
 
-                       if (ferror(fp))
-                               perror(name);
 
-                       fclose(fp);
+       /* argv[(optind)..(argc-1)] should be names of file to process. If no
+        * files were specified or '-' was specified, take input from stdin.
+        * Otherwise, we process all the files specified. */
+       if (argv[optind] == NULL || (strcmp(argv[optind], "-") == 0)) {
+               process_file(stdin);
+       }
+       else {
+               int i;
+               FILE *file;
+               for (i = optind; i < argc; i++) {
+                       file = fopen(argv[i], "r");
+                       if (file == NULL) {
+                               fprintf(stderr, "sed: %s: %s\n", argv[i], strerror(errno));
+                       } else {
+                               process_file(file);
+                               fclose(file);
+                       }
                }
        }
-       return(TRUE);
-}
+       
+       exit_sed(0, NULL);
 
+       /* not reached */
+       return 0;
+}
 
-/* END CODE */
+#ifdef TEST_SED
+int main(int argc, char **argv)
+{
+       return sed_main(argc, argv);
+}
+#endif