Changes to grep/src/grep.c

[Charles Levert]

Index: grep/src/grep.c
diff -u grep/src/grep.c:1.105 grep/src/grep.c:1.106
--- grep/src/grep.c:1.105       Tue Jun 21 14:18:04 2005
+++ grep/src/grep.c     Tue Jun 21 14:58:50 2005
@@ -79,6 +79,9 @@
 /* If nonzero, use grep_color marker.  */
 static int color_option;
 
+/* If nonzero, do pseudo-markup instead of actual colors.  */
+static int pseudo_markup;
+
 /* If nonzero, show only the part of a line matching the expression. */
 static int only_matching;
 
@@ -125,9 +128,18 @@
         This only leaves red, magenta, green, and cyan (and their bold
         counterparts) and possibly bold blue.  */
 /* The color string used for matched text.
-   The user can overwrite it using the environment variable GREP_COLOR.  */
+   The user can overwrite it using the deprecated
+   environment variable GREP_COLOR or the new GREP_COLORS.  */
 static const char *grep_color = "01;31";       /* bold red */
 
+/* Other colors.  Defaults look damn good.  */
+static const char *filename_color = "35";      /* magenta */
+static const char *line_num_color = "32";      /* green */
+static const char *byte_num_color = "32";      /* green */
+static const char *sep_color      = "36";      /* cyan */
+static const char *mlines_color   = "";                /* default color pair */
+static const char *context_color  = "";                /* default color pair */
+
 /* Select Graphic Rendition (SGR, "\33[...m") strings.  */
 /* Also Erase in Line (EL) to Right ("\33[K") by default.  */
 /*    Why have EL to Right after SGR?
@@ -185,8 +197,10 @@
       It would be impractical for GNU grep to become a full-fledged
       terminal program linked against ncurses or the like, so it will
       not detect terminfo(5) capabilities.  */
-#define SGR_START "\33[%sm\33[K"
-#define SGR_END   "\33[m\33[K"
+static const char *sgr_start = "\33[%sm\33[K";
+#define SGR_START  sgr_start
+static const char *sgr_end   = "\33[m\33[K";
+#define SGR_END    sgr_end
 
 /* SGR utility macros.  */
 #define PR_SGR_FMT(fmt, s) do { if (*(s)) printf((fmt), (s)); } while (0)
@@ -197,6 +211,61 @@
 #define PR_SGR_START_IF(s) PR_SGR_FMT_IF(SGR_START, (s))
 #define PR_SGR_END_IF(s)   PR_SGR_FMT_IF(SGR_END,   (s))
 
+struct color_cap
+  {
+    const char *name;
+    const char **var;
+    const char *(*fct)(void);
+  };
+
+const char *
+color_cap_ne_fct(void)
+{
+  if (pseudo_markup)
+    return "makes no sense after the \"xm\" capability; ignored";
+
+  sgr_start = "\33[%sm";
+  sgr_end   = "\33[m";
+
+  return NULL;
+}
+
+const char *
+color_cap_xm_fct(void)
+{
+  /* This experimental feature should stay undocumented for now.  */
+  pseudo_markup = 1;
+
+  sgr_start = "<grep:%s>";
+  sgr_end   = "</grep:%s>";
+
+  /* The user can just redefine them to the empty string afterwards.  */
+  grep_color     = "matched-text";
+  filename_color = "filename";
+  line_num_color = "line-number";
+  byte_num_color = "byte-offset";
+  sep_color      = "separator";
+  mlines_color   = "matching-line";
+  context_color  = "context-line";
+
+  return NULL;
+}
+
+/* For GREP_COLORS.  */
+static struct color_cap color_dict[] =
+  {
+    { "mt", &grep_color,       NULL },                 /* matched text */
+    { "fn", &filename_color,   NULL },                 /* filename */
+    { "ln", &line_num_color,   NULL },                 /* line number */
+    { "bn", &byte_num_color,   NULL },                 /* byte (sic) offset */
+    { "se", &sep_color,                NULL },                 /* separator */
+    { "ml", &mlines_color,     NULL },                 /* matching lines */
+    { "cx", &context_color,    NULL },                 /* context lines */
+    { "ne", NULL,              color_cap_ne_fct },     /* no EL on SGR_* */
+    { "xm", NULL,              color_cap_xm_fct },     /* pseudo-markup */
+    { NULL, NULL,              NULL }
+  };
+
 static struct exclude *excluded_patterns;
 static struct exclude *included_patterns;
 /* Short options.  */
@@ -604,6 +673,24 @@
   lastnl = lim;
 }
 
+/* Print the current filename.  */
+static void
+print_filename (void)
+{
+  PR_SGR_START_IF(filename_color);
+  fputs(filename, stdout);
+  PR_SGR_END_IF(filename_color);
+}
+
+/* Print a character separator.  */
+static void
+print_sep (char sep)
+{
+  PR_SGR_START_IF(sep_color);
+  fputc(sep, stdout);
+  PR_SGR_END_IF(sep_color);
+}
+
 /* Print a byte offset, followed by a character separator.  */
 static void
 print_offset_sep (uintmax_t pos, char sep)
@@ -816,7 +903,12 @@
       /* We print the SEP_STR_CHUNK separator only if our output is
         discontiguous from the last output in the file. */
       if ((out_before || out_after) && used && p != lastout)
-       puts (SEP_STR_CHUNK);
+       {
+         PR_SGR_START_IF(sep_color);
+         fputs (SEP_STR_CHUNK, stdout);
+         PR_SGR_END_IF(sep_color);
+         fputc('\n', stdout);
+       }
 
       while (p < beg)
        {
@@ -1122,13 +1214,22 @@
       if (count_matches)
        {
          if (out_file)
-           printf ("%s%c", filename, SEP_CHAR_MATCH & filename_mask);
+           {
+             print_filename();
+             if (filename_mask)
+               print_sep(SEP_CHAR_MATCH);
+             else
+               fputc(0, stdout);
+           }
          printf ("%d\n", count);
        }
 
       status = !count;
       if (list_files == 1 - 2 * status)
-       printf ("%s%c", filename, '\n' & filename_mask);
+       {
+         print_filename();
+         fputc('\n' & filename_mask, stdout);
+       }
 
       if (! file)
        {
@@ -1447,6 +1548,91 @@
   return opt;
 }
 
+/* Parse GREP_COLORS.  The  default would look like:
+     GREP_COLORS='mt=01;31:ml=:cx=:fn=35:ln=32:bn=32:se=36'
+   No character escaping is needed or supported.  */
+static void
+parse_grep_colors (void)
+{
+  const char *p;
+  char *q;
+  char *name;
+  char *val;
+
+  p = getenv("GREP_COLORS"); /* Plural! */
+  if (p == NULL || *p == '\0')
+    return;
+
+  /* Work off a writable copy.  */
+  q = xmalloc(strlen(p) + 1);
+  if (q == NULL)
+    return;
+  strcpy(q, p);
+
+  name = q;
+  val = NULL;
+  /* From now on, be well-formed or you're gone.  */
+  for (;;)
+    if (*q == ':' || *q == '\0')
+      {
+       char c = *q;
+       struct color_cap *cap;
+
+       *q++ = '\0'; /* Terminate name or val.  */
+       /* Empty name without val (empty cap)
+        * won't match and will be ignored.  */
+       for (cap = color_dict; cap->name; cap++)
+         if (strcmp(cap->name, name) == 0)
+           break;
+       /* If name unknown, go on for forward compatibility.  */
+       if (cap->name)
+         if (cap->var)
+           {
+             if (val)
+               *(cap->var) = val;
+             else
+               fprintf(stderr,
+                       _("%s: In GREP_COLORS=\"%s\", the \"%s\" capacity needs 
a value (\"=...\"); skipped.\n"),
+                       program_name, p, name);
+           }
+         else if (val)
+           fprintf(stderr,
+                   _("%s: In GREP_COLORS=\"%s\", the \"%s\" capacity is 
boolean and cannot take a value (\"=%s\"); skipped.\n"),
+                   program_name, p, name, val);
+       if (cap->fct)
+         {
+           const char *err_str = cap->fct();
+
+           if (err_str)
+             fprintf(stderr,
+                     _("%s: In GREP_COLORS=\"%s\", the \"%s\" capacity %s.\n"),
+                     program_name, p, name, err_str);
+         }
+       if (c == '\0')
+         return;
+       name = q;
+       val = NULL;
+      }
+    else if (*q == '=')
+      {
+       if (q == name || val)
+         goto ill_formed;
+       *q++ = '\0'; /* Terminate name.  */
+       val = q; /* Can be the empty string.  */
+      }
+    else if (val == NULL)
+      q++; /* Accumulate name.  */
+    else if (*q == ';' || (*q >= '0' && *q <= '9'))
+      q++; /* Accumulate val.  Protect the terminal from being sent crap.  */
+    else
+      goto ill_formed;
+
+ ill_formed:
+  fprintf(stderr,
+         _("%s: Stopped processing of ill-formed GREP_COLORS=\"%s\" at 
remaining substring \"%s\".\n"),
+         program_name, p, q);
+}
+
 int
 main (int argc, char **argv)
 {
@@ -1827,9 +2013,13 @@
 
   if (color_option)
     {
+      /* Legacy.  */
       char *userval = getenv ("GREP_COLOR");
       if (userval != NULL && *userval != '\0')
        grep_color = userval;
+
+      /* New GREP_COLORS has priority.  */
+      parse_grep_colors();
     }
 
   if (! matcher)