Merge branch 'pb/regex'

* pb/regex:
  On some platforms, certain headers need to be included before regex.h
  Support for pickaxe matching regular expressions

Documentation/diff-options.txt

@@ -69,6 +69,10 @@
 	changeset, not just the files that contain the change
 	in <string>.
 
+--pickaxe-regex::
+	Make the <string> not a plain string but an extended POSIX
+	regex to match.
+
 -O<orderfile>::
 	Output the patch in the order specified in the
 	<orderfile>, which has one shell glob pattern per line.

diff.c

@@ -883,6 +883,8 @@ int diff_opt_parse(struct diff_options *options, const char **av, int ac)
 		options->filter = arg + 14;
 	else if (!strcmp(arg, "--pickaxe-all"))
 		options->pickaxe_opts = DIFF_PICKAXE_ALL;
+	else if (!strcmp(arg, "--pickaxe-regex"))
+		options->pickaxe_opts = DIFF_PICKAXE_REGEX;
 	else if (!strncmp(arg, "-B", 2)) {
 		if ((options->break_opt =
 		     diff_scoreopt_parse(arg)) == -1)

diff.h

@@ -102,6 +102,7 @@ extern int diff_setup_done(struct diff_options *);
 #define DIFF_DETECT_COPY	2
 
 #define DIFF_PICKAXE_ALL	1
+#define DIFF_PICKAXE_REGEX	2
 
 extern void diffcore_std(struct diff_options *);
 

diffcore-pickaxe.c

@@ -5,8 +5,11 @@
 #include "diff.h"
 #include "diffcore.h"
 
+#include <regex.h>
+
 static unsigned int contains(struct diff_filespec *one,
-			     const char *needle, unsigned long len)
+			     const char *needle, unsigned long len,
+			     regex_t *regexp)
 {
 	unsigned int cnt;
 	unsigned long offset, sz;
@@ -18,15 +21,28 @@ static unsigned int contains(struct diff_filespec *one,
 	data = one->data;
 	cnt = 0;
 
-	/* Yes, I've heard of strstr(), but the thing is *data may
-	 * not be NUL terminated.  Sue me.
-	 */
-	for (offset = 0; offset + len <= sz; offset++) {
-		/* we count non-overlapping occurrences of needle */
-		if (!memcmp(needle, data + offset, len)) {
-			offset += len - 1;
+	if (regexp) {
+		regmatch_t regmatch;
+		int flags = 0;
+
+		while (*data && !regexec(regexp, data, 1, &regmatch, flags)) {
+			flags |= REG_NOTBOL;
+			data += regmatch.rm_so;
+			if (*data) data++;
 			cnt++;
 		}
+
+	} else { /* Classic exact string match */
+		/* Yes, I've heard of strstr(), but the thing is *data may
+		 * not be NUL terminated.  Sue me.
+		 */
+		for (offset = 0; offset + len <= sz; offset++) {
+			/* we count non-overlapping occurrences of needle */
+			if (!memcmp(needle, data + offset, len)) {
+				offset += len - 1;
+				cnt++;
+			}
+		}
 	}
 	return cnt;
 }
@@ -36,10 +52,24 @@ void diffcore_pickaxe(const char *needle, int opts)
 	struct diff_queue_struct *q = &diff_queued_diff;
 	unsigned long len = strlen(needle);
 	int i, has_changes;
+	regex_t regex, *regexp = NULL;
 	struct diff_queue_struct outq;
 	outq.queue = NULL;
 	outq.nr = outq.alloc = 0;
 
+	if (opts & DIFF_PICKAXE_REGEX) {
+		int err;
+		err = regcomp(&regex, needle, REG_EXTENDED | REG_NEWLINE);
+		if (err) {
+			/* The POSIX.2 people are surely sick */
+			char errbuf[1024];
+			regerror(err, &regex, errbuf, 1024);
+			regfree(&regex);
+			die("invalid pickaxe regex: %s", errbuf);
+		}
+		regexp = &regex;
+	}
+
 	if (opts & DIFF_PICKAXE_ALL) {
 		/* Showing the whole changeset if needle exists */
 		for (i = has_changes = 0; !has_changes && i < q->nr; i++) {
@@ -48,16 +78,16 @@ void diffcore_pickaxe(const char *needle, int opts)
 				if (!DIFF_FILE_VALID(p->two))
 					continue; /* ignore unmerged */
 				/* created */
-				if (contains(p->two, needle, len))
+				if (contains(p->two, needle, len, regexp))
 					has_changes++;
 			}
 			else if (!DIFF_FILE_VALID(p->two)) {
-				if (contains(p->one, needle, len))
+				if (contains(p->one, needle, len, regexp))
 					has_changes++;
 			}
 			else if (!diff_unmodified_pair(p) &&
-				 contains(p->one, needle, len) !=
-				 contains(p->two, needle, len))
+				 contains(p->one, needle, len, regexp) !=
+				 contains(p->two, needle, len, regexp))
 				has_changes++;
 		}
 		if (has_changes)
@@ -80,16 +110,16 @@ void diffcore_pickaxe(const char *needle, int opts)
 				if (!DIFF_FILE_VALID(p->two))
 					; /* ignore unmerged */
 				/* created */
-				else if (contains(p->two, needle, len))
+				else if (contains(p->two, needle, len, regexp))
 					has_changes = 1;
 			}
 			else if (!DIFF_FILE_VALID(p->two)) {
-				if (contains(p->one, needle, len))
+				if (contains(p->one, needle, len, regexp))
 					has_changes = 1;
 			}
 			else if (!diff_unmodified_pair(p) &&
-				 contains(p->one, needle, len) !=
-				 contains(p->two, needle, len))
+				 contains(p->one, needle, len, regexp) !=
+				 contains(p->two, needle, len, regexp))
 				has_changes = 1;
 
 			if (has_changes)
@@ -98,6 +128,10 @@ void diffcore_pickaxe(const char *needle, int opts)
 				diff_free_filepair(p);
 		}
 
+	if (opts & DIFF_PICKAXE_REGEX) {
+		regfree(&regex);
+	}
+
 	free(q->queue);
 	*q = outq;
 	return;