sed: fix handling of files not ending in '\n'
authorDenis Vlasenko <vda.linux@googlemail.com>
Sat, 2 Dec 2006 20:12:12 +0000 (20:12 -0000)
committerDenis Vlasenko <vda.linux@googlemail.com>
Sat, 2 Dec 2006 20:12:12 +0000 (20:12 -0000)
editors/sed.c

index 630d6d7..94368aa 100644 (file)
@@ -81,6 +81,7 @@ typedef struct sed_cmd_s {
        unsigned int invert:1;          /* the '!' after the address */
        unsigned int in_match:1;        /* Next line also included in match? */
        unsigned int sub_p:1;           /* (s) print option */
+
        int last_char;                  /* Last line written by (sw) had no '\n' */
 
        /* GENERAL FIELDS */
@@ -715,12 +716,9 @@ static void add_input_file(FILE *file)
 static char *get_next_line(int *last_char)
 {
        char *temp = NULL;
-       int len;
-
-       /* will be returned if last line in the file
-        * doesn't end with either '\n' or '\0' */
-       *last_char = 0x100;
+       int len, lc;
 
+       lc = 0;
        flush_append();
        while (bbg.current_input_file < bbg.input_file_count) {
                temp = bb_get_chunk_from_file(
@@ -730,18 +728,27 @@ static char *get_next_line(int *last_char)
                        char c = temp[len-1];
                        if (c == '\n' || c == '\0') {
                                temp[len-1] = '\0';
-                               *last_char = (unsigned char)c;
+                               lc |= (unsigned char)c;
+                               break;
                        }
+                       /* will be returned if last line in the file
+                        * doesn't end with either '\n' or '\0' */
+                       lc |= 0x100;
                        break;
                }
                /* Close this file and advance to next one */
                fclose(bbg.input_file_list[bbg.current_input_file++]);
+               /* "this is the first line from new input file" */
+               lc |= 0x200;
        }
+       *last_char = lc;
        return temp;
 }
 
 /* Output line of text. */
 /* Note:
+ * The tricks with 0x200 and last_puts_char are there to emulate gnu sed.
+ * Without them, we had this:
  * echo -n thingy >z1
  * echo -n again >z2
  * >znull
@@ -750,13 +757,26 @@ static char *get_next_line(int *last_char)
  * 00000000  74 68 7a 6e 67 79 0a 61  67 61 7a 6e              |thzngy.agazn|
  * bbox:
  * 00000000  74 68 7a 6e 67 79 61 67  61 7a 6e                 |thzngyagazn|
- * I am not sure that bbox is wrong here...
  */
 
 static int puts_maybe_newline(char *s, FILE *file, int prev_last_char, int last_char)
 {
+       static char last_puts_char;
+
+       /* Is this a first line from new file
+        * and old file didn't end with '\n'? */
+       if ((last_char & 0x200) && last_puts_char != '\n') {
+               fputc('\n', file);
+               last_puts_char = '\n';
+       }
        fputs(s, file);
-       if (last_char < 0x100) fputc(last_char, file);
+       /* 'x': we don't care what is it, but we know it isn't '\n' */
+       if (s[0]) last_puts_char = 'x';
+       if (!(last_char & 0x100)) { /* had trailing '\n' or '\0'? */
+               last_char &= 0xff;
+               fputc(last_char, file);
+               last_puts_char = last_char;
+       }
 
        if (ferror(file)) {
                xfunc_error_retval = 4;  /* It's what gnu sed exits with... */
@@ -1047,7 +1067,7 @@ restart:
                                        strcat(pattern_space, "\n");
                                        if (bbg.hold_space)
                                                strcat(pattern_space, bbg.hold_space);
-                                       last_char = 0x100;
+                                       last_char = '\n';
 
                                        break;
                                }
@@ -1079,7 +1099,7 @@ restart:
                                {
                                        char *tmp = pattern_space;
                                        pattern_space = bbg.hold_space ? : xzalloc(1);
-                                       last_char = 0x100;
+                                       last_char = '\n';
                                        bbg.hold_space = tmp;
                                        break;
                                }