Minor code reorg: Changed the interface to index_of_next_unescaped_slash to an

interface that seems a little more sensible to me. Also broke out s///
expression parsing into it's own subroutine.

diff --git a/editors/sed.c b/editors/sed.c
index 21f8681..8ae34f8 100644 (file)
--- a/editors/sed.c
+++ b/editors/sed.c
@@ -162,7 +162,7 @@ static char *trim_str(const char *str)
  * 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)
+static int index_of_next_unescaped_slash(const char *str, int idx)
 {
        do {
                idx++;
@@ -196,7 +196,7 @@ static int get_address(const char *str, int *line, regex_t **regex)
                idx++;
        }
        else if (my_str[idx] == '/') {
-               idx = index_of_next_unescaped_slash(idx, my_str);
+               idx = index_of_next_unescaped_slash(my_str, idx);
                if (idx == -1)
                        fatalError("unterminated match expression\n");
                my_str[idx] = '\0';
@@ -222,6 +222,59 @@ static char *strdup_substr(const char *str, int start, int end)
        return newstr;
 }
 
+static void parse_subst_cmd(struct sed_cmd *sed_cmd, const char *substr)
+{
+       int oldidx, cflags = REG_NEWLINE;
+       char *match;
+       int idx = 0;
+
+       /*
+        * the string that gets passed to this function should look like this:
+        *    s/match/replace/gI
+        *    ||     |        ||
+        *    mandatory       optional
+        *
+        *    (all three of the '/' slashes are mandatory)
+        */
+
+       /* verify that the 's' is followed by a 'slash' */
+       if (substr[++idx] != '/')
+               fatalError("bad format in substitution expression\n");
+
+       /* save the match string */
+       oldidx = idx+1;
+       idx = index_of_next_unescaped_slash(substr, idx);
+       if (idx == -1)
+               fatalError("bad format in substitution expression\n");
+       match = strdup_substr(substr, oldidx, idx);
+
+       /* save the replacement string */
+       oldidx = idx+1;
+       idx = index_of_next_unescaped_slash(substr, idx);
+       if (idx == -1)
+               fatalError("bad format in substitution expression\n");
+       sed_cmd->replace = strdup_substr(substr, oldidx, idx);
+
+       /* process the flags */
+       while (substr[++idx]) {
+               switch (substr[idx]) {
+               case 'g':
+                       sed_cmd->sub_g = 1;
+                       break;
+               case 'I':
+                       cflags |= REG_ICASE;
+                       break;
+               default:
+                       fatalError("bad option in substitution expression\n");
+               }
+       }
+               
+       /* compile the regex */
+       sed_cmd->sub_match = (regex_t *)xmalloc(sizeof(regex_t));
+       xregcomp(sed_cmd->sub_match, match, cflags);
+       free(match);
+}
+
 static void parse_cmd_str(struct sed_cmd *sed_cmd, const char *cmdstr)
 {
        int idx = 0;
@@ -246,53 +299,10 @@ static void parse_cmd_str(struct sed_cmd *sed_cmd, const char *cmdstr)
        if (!strchr("pds", cmdstr[idx])) /* <-- XXX add new commands here */
                fatalError("invalid command\n");
        sed_cmd->cmd = cmdstr[idx];
-       /* special-case handling for 's' */
-       if (sed_cmd->cmd == 's') {
-               int oldidx, cflags = REG_NEWLINE;
-               char *match;
-               /* format for substitution is:
-                *    s/match/replace/gI
-                *    |               ||
-                *    mandatory       optional
-                */
-
-               /* verify that we have an 's' followed by a 'slash' */
-               if (cmdstr[++idx] != '/')
-                       fatalError("bad format in substitution expression\n");
-
-               /* save the match string */
-               oldidx = idx+1;
-               idx = index_of_next_unescaped_slash(idx, cmdstr);
-               if (idx == -1)
-                       fatalError("bad format in substitution expression\n");
-               match = strdup_substr(cmdstr, oldidx, idx);
 
-               /* save the replacement string */
-               oldidx = idx+1;
-               idx = index_of_next_unescaped_slash(idx, cmdstr);
-               if (idx == -1)
-                       fatalError("bad format in substitution expression\n");
-               sed_cmd->replace = strdup_substr(cmdstr, oldidx, idx);
-
-               /* process the flags */
-               while (cmdstr[++idx]) {
-                       switch (cmdstr[idx]) {
-                       case 'g':
-                               sed_cmd->sub_g = 1;
-                               break;
-                       case 'I':
-                               cflags |= REG_ICASE;
-                               break;
-                       default:
-                               fatalError("bad option in substitution expression\n");
-                       }
-               }
-                       
-               /* compile the regex */
-               sed_cmd->sub_match = (regex_t *)xmalloc(sizeof(regex_t));
-               xregcomp(sed_cmd->sub_match, match, cflags);
-               free(match);
-       }
+       /* special-case handling for (s)ubstitution */
+       if (sed_cmd->cmd == 's')
+               parse_subst_cmd(sed_cmd, &cmdstr[idx]);
 }
 
 static void add_cmd_str(const char *cmdstr)

diff --git a/sed.c b/sed.c
index 21f8681..8ae34f8 100644 (file)
--- a/sed.c
+++ b/sed.c
@@ -162,7 +162,7 @@ static char *trim_str(const char *str)
  * 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)
+static int index_of_next_unescaped_slash(const char *str, int idx)
 {
        do {
                idx++;
@@ -196,7 +196,7 @@ static int get_address(const char *str, int *line, regex_t **regex)
                idx++;
        }
        else if (my_str[idx] == '/') {
-               idx = index_of_next_unescaped_slash(idx, my_str);
+               idx = index_of_next_unescaped_slash(my_str, idx);
                if (idx == -1)
                        fatalError("unterminated match expression\n");
                my_str[idx] = '\0';
@@ -222,6 +222,59 @@ static char *strdup_substr(const char *str, int start, int end)
        return newstr;
 }
 
+static void parse_subst_cmd(struct sed_cmd *sed_cmd, const char *substr)
+{
+       int oldidx, cflags = REG_NEWLINE;
+       char *match;
+       int idx = 0;
+
+       /*
+        * the string that gets passed to this function should look like this:
+        *    s/match/replace/gI
+        *    ||     |        ||
+        *    mandatory       optional
+        *
+        *    (all three of the '/' slashes are mandatory)
+        */
+
+       /* verify that the 's' is followed by a 'slash' */
+       if (substr[++idx] != '/')
+               fatalError("bad format in substitution expression\n");
+
+       /* save the match string */
+       oldidx = idx+1;
+       idx = index_of_next_unescaped_slash(substr, idx);
+       if (idx == -1)
+               fatalError("bad format in substitution expression\n");
+       match = strdup_substr(substr, oldidx, idx);
+
+       /* save the replacement string */
+       oldidx = idx+1;
+       idx = index_of_next_unescaped_slash(substr, idx);
+       if (idx == -1)
+               fatalError("bad format in substitution expression\n");
+       sed_cmd->replace = strdup_substr(substr, oldidx, idx);
+
+       /* process the flags */
+       while (substr[++idx]) {
+               switch (substr[idx]) {
+               case 'g':
+                       sed_cmd->sub_g = 1;
+                       break;
+               case 'I':
+                       cflags |= REG_ICASE;
+                       break;
+               default:
+                       fatalError("bad option in substitution expression\n");
+               }
+       }
+               
+       /* compile the regex */
+       sed_cmd->sub_match = (regex_t *)xmalloc(sizeof(regex_t));
+       xregcomp(sed_cmd->sub_match, match, cflags);
+       free(match);
+}
+
 static void parse_cmd_str(struct sed_cmd *sed_cmd, const char *cmdstr)
 {
        int idx = 0;
@@ -246,53 +299,10 @@ static void parse_cmd_str(struct sed_cmd *sed_cmd, const char *cmdstr)
        if (!strchr("pds", cmdstr[idx])) /* <-- XXX add new commands here */
                fatalError("invalid command\n");
        sed_cmd->cmd = cmdstr[idx];
-       /* special-case handling for 's' */
-       if (sed_cmd->cmd == 's') {
-               int oldidx, cflags = REG_NEWLINE;
-               char *match;
-               /* format for substitution is:
-                *    s/match/replace/gI
-                *    |               ||
-                *    mandatory       optional
-                */
-
-               /* verify that we have an 's' followed by a 'slash' */
-               if (cmdstr[++idx] != '/')
-                       fatalError("bad format in substitution expression\n");
-
-               /* save the match string */
-               oldidx = idx+1;
-               idx = index_of_next_unescaped_slash(idx, cmdstr);
-               if (idx == -1)
-                       fatalError("bad format in substitution expression\n");
-               match = strdup_substr(cmdstr, oldidx, idx);
 
-               /* save the replacement string */
-               oldidx = idx+1;
-               idx = index_of_next_unescaped_slash(idx, cmdstr);
-               if (idx == -1)
-                       fatalError("bad format in substitution expression\n");
-               sed_cmd->replace = strdup_substr(cmdstr, oldidx, idx);
-
-               /* process the flags */
-               while (cmdstr[++idx]) {
-                       switch (cmdstr[idx]) {
-                       case 'g':
-                               sed_cmd->sub_g = 1;
-                               break;
-                       case 'I':
-                               cflags |= REG_ICASE;
-                               break;
-                       default:
-                               fatalError("bad option in substitution expression\n");
-                       }
-               }
-                       
-               /* compile the regex */
-               sed_cmd->sub_match = (regex_t *)xmalloc(sizeof(regex_t));
-               xregcomp(sed_cmd->sub_match, match, cflags);
-               free(match);
-       }
+       /* special-case handling for (s)ubstitution */
+       if (sed_cmd->cmd == 's')
+               parse_subst_cmd(sed_cmd, &cmdstr[idx]);
 }
 
 static void add_cmd_str(const char *cmdstr)