0001-diff.c-Add-new-option-only-that-matches.patch

From 6f5b9efbd09b44b25cd6bdb23a8593337075a919 Mon Sep 17 00:00:00 2001
From: Daniel Hilst Selli <danielhilst@gmail.com>
Date: Sat, 4 Oct 2014 03:26:01 +0000
Subject: [PATCH] diff.c Add new option --only-that-matches

This option is the oposite of --exclude, only files
that match the regex passed to it will be parsed

The thread on bug-diffutils: http://lists.gnu.org/archive/html/bug-diffutils/2014-10/msg00000.html
---
 src/diff.c | 15 +++++++++++++++
 src/diff.h |  2 ++
 src/dir.c  |  7 +++++++
 3 files changed, 24 insertions(+)

diff --git a/src/diff.c b/src/diff.c
index 397815e..b5992e2 100644
--- a/src/diff.c
+++ b/src/diff.c@
@ -126,6 +126,7 @@ enum
   SUPPRESS_COMMON_LINES_OPTION,
   TABSIZE_OPTION,
   TO_FILE_OPTION,
+  ONLY_THAT_MATCHES_OPTION,

   /* These options must be in sequence.  */
   UNCHANGED_LINE_FORMAT_OPTION,
@@ -191,6 +192,7 @@ static struct option const longopts[] =
   {"normal", 0, 0, NORMAL_OPTION},
   {"old-group-format", 1, 0, OLD_GROUP_FORMAT_OPTION},
   {"old-line-format", 1, 0, OLD_LINE_FORMAT_OPTION},
+  {"only-that-matches", 1, 0, ONLY_THAT_MATCHES_OPTION},
   {"paginate", 0, 0, 'l'},
   {"rcs", 0, 0, 'n'},
   {"recursive", 0, 0, 'r'},
@@ -609,6 +611,19 @@ main (int argc, char **argv)
      specify_value (&to_file, optarg, "--to-file");
      break;

+        case ONLY_THAT_MATCHES_OPTION:
+          {
+            char regex_error[256];
+            int rc = regcomp(&otm_regex, optarg, REG_NOSUB | REG_EXTENDED);
+            if (rc)
+              {
+                regerror(rc, &otm_regex, regex_error, 256);
+                error(EXIT_TROUBLE, 0, "Can't compile regex %s: %s", optarg, regex_error);
+                abort();
+              }
+          }
+          break;
+
    case UNCHANGED_LINE_FORMAT_OPTION:
    case OLD_LINE_FORMAT_OPTION:
    case NEW_LINE_FORMAT_OPTION:
diff --git a/src/diff.h b/src/diff.h
index e9f0471..5c91bfa 100644
--- a/src/diff.h
+++ b/src/diff.h
@@ -328,6 +328,8 @@ XTERN FILE *outfile;

 /* Declare various functions.  */

+XTERN regex_t otm_regex;
+
 /* analyze.c */
 extern int diff_2_files (struct comparison *);

diff --git a/src/dir.c b/src/dir.c
index d3b0a2d..d6207a8 100644
--- a/src/dir.c
+++ b/src/dir.c
@@ -90,12 +90,19 @@ dir_read (struct file_data const *dir, struct dirdata *dirdata)
    {
      char *d_name = next->d_name;
      size_t d_size = _D_EXACT_NAMLEN (next) + 1;
+          int rmatch;

      /* Ignore "." and "..".  */
      if (d_name[0] == '.'
          && (d_name[1] == 0 || (d_name[1] == '.' && d_name[2] == 0)))
        continue;

+          rmatch = regexec(&otm_regex, d_name, 0, 0, 0);
+          if (rmatch == REG_NOMATCH)
+            continue;
+          else if (rmatch)
+              fatal("Out of memory while executing regexp");
+
      if (excluded_file_name (excluded, d_name))
        continue;

--
2.1.0