X-Git-Url: https://git.verplant.org/?a=blobdiff_plain;f=show-diff.c;h=32d2fceaff2a3fb8e3e52d4708946e205ab41d76;hb=5a6ad74623571a1479af7914ec16783a9566e4b2;hp=bc3791aaaab22f345bcf2478fdced16cd5e1bdce;hpb=e2e5e98a40d6ed04b7acf791cc2243ff32923db3;p=git.git

diff --git a/show-diff.c b/show-diff.c
index bc3791aa..32d2fcea 100644
--- a/show-diff.c
+++ b/show-diff.c
@@ -5,70 +5,124 @@
  */
 #include "cache.h"
 
-static void show_differences(char *name, 
-	void *old_contents, unsigned long long old_size)
+static char *diff_cmd = "diff -L 'a/%s' -L 'b/%s' -p -u - '%s'";
+
+/* Help to copy the thing properly quoted for the shell safety.
+ * any single quote is replaced with '\'', and the caller is
+ * expected to enclose the result within a single quote pair.
+ *
+ * E.g.
+ *  original     sq_expand     result
+ *  name     ==> name      ==> 'name'
+ *  a b      ==> a b       ==> 'a b'
+ *  a'b      ==> a'\''b    ==> 'a'\''b'
+ *
+ * NOTE! The returned memory belongs to this function so
+ * do not free it.
+ */
+static char *sq_expand(char *src)
+{
+	static char *buf = NULL;
+	int cnt, c;
+	char *cp;
+
+	/* count bytes needed to store the quoted string. */ 
+	for (cnt = 1, cp = src; *cp; cnt++, cp++)
+		if (*cp == '\'')
+			cnt += 3;
+
+	if (! (buf = malloc(cnt)))
+	    return buf;
+	cp = buf;
+	while ((c = *src++)) {
+		if (c != '\'')
+			*cp++ = c;
+		else {
+			cp = strcpy(cp, "'\\''");
+			cp += 4;
+		}
+	}
+	*cp = 0;
+	return buf;
+}
+
+static void show_differences(char *name, char *label, void *old_contents,
+			     unsigned long long old_size)
 {
-	static char cmd[1000];
 	FILE *f;
+	char *name_sq = sq_expand(name);
+	char *label_sq = (name != label) ? sq_expand(label) : name_sq;
+	int cmd_size = strlen(name_sq) +
+		strlen(label_sq) * 2 + strlen(diff_cmd);
+	char *cmd = malloc(cmd_size);
 
-	snprintf(cmd, sizeof(cmd), "diff -L %s -u -N  - %s", name, name);
+	fflush(stdout);
+	snprintf(cmd, cmd_size, diff_cmd, label_sq, label_sq, name_sq);
 	f = popen(cmd, "w");
 	if (old_size)
 		fwrite(old_contents, old_size, 1, f);
 	pclose(f);
+	if (label_sq != name_sq)
+		free(label_sq);
+	free(name_sq);
+	free(cmd);
 }
 
 static void show_diff_empty(struct cache_entry *ce)
 {
 	char *old;
 	unsigned long int size;
-	int lines=0;
-	unsigned char type[20], *p, *end;
+	unsigned char type[20];
 
 	old = read_sha1_file(ce->sha1, type, &size);
-	if (size > 0) {
-		int startline = 1;
-		int c = 0;
-
-		printf("--- %s\n", ce->name);
-		printf("+++ %s\n", ce->name);
-		p = old;
-		end = old + size; 
-		while (p < end)
-			if (*p++ == '\n')
-				lines ++;
-		printf("@@ -1,%d +0,0 @@\n", lines);
-		p = old;
-		while (p < end) {
-			c = *p++;
-			if (startline) {
-				putchar('-');
-				startline = 0;
-			} 
-			putchar(c);
-			if (c == '\n')
-				startline = 1;
-		}
-		if (c!='\n')
-			printf("\n");
-		fflush(stdout);
+	if (! old) {
+		error("unable to read blob object for %s (%s)", ce->name,
+		      sha1_to_hex(ce->sha1));
+		return;
 	}
+	show_differences("/dev/null", ce->name, old, size);
+}
+
+static const char *show_diff_usage = "show-diff [-q] [-s] [-z] [paths...]";
+
+static int matches_pathspec(struct cache_entry *ce, char **spec, int cnt)
+{
+	int i;
+	int namelen = ce_namelen(ce);
+	for (i = 0; i < cnt; i++) {
+		int speclen = strlen(spec[i]);
+		if (! strncmp(spec[i], ce->name, speclen) &&
+		    speclen <= namelen &&
+		    (ce->name[speclen] == 0 ||
+		     ce->name[speclen] == '/'))
+			return 1;
+	}
+	return 0;
 }
 
 int main(int argc, char **argv)
 {
 	int silent = 0;
+	int silent_on_nonexisting_files = 0;
+	int machine_readable = 0;
 	int entries = read_cache();
 	int i;
 
-	while (argc-- > 1) {
-		if (!strcmp(argv[1], "-s")) {
-			silent = 1;
-			continue;
-		}
-		usage("show-diff [-s]");
+	while (1 < argc && argv[1][0] == '-') {
+		if (!strcmp(argv[1], "-s"))
+			silent_on_nonexisting_files = silent = 1;
+		else if (!strcmp(argv[1], "-q"))
+			silent_on_nonexisting_files = 1;
+		else if (!strcmp(argv[1], "-z"))
+			machine_readable = 1;
+		else
+			usage(show_diff_usage);
+		argv++; argc--;
 	}
 
+	/* At this point, if argc == 1, then we are doing everything.
+	 * Otherwise argv[1] .. argv[argc-1] have the explicit paths.
+	 */
 	if (entries < 0) {
 		perror("read_cache");
 		exit(1);
@@ -76,31 +130,59 @@ int main(int argc, char **argv)
 	for (i = 0; i < entries; i++) {
 		struct stat st;
 		struct cache_entry *ce = active_cache[i];
-		int n, changed;
+		int changed;
 		unsigned long size;
 		char type[20];
-		void *new;
+		void *old;
 
+		if (1 < argc &&
+		    ! matches_pathspec(ce, argv+1, argc-1))
+			continue;
+
+		if (ce_stage(ce)) {
+			if (machine_readable)
+				printf("U %s%c", ce->name, 0);
+			else
+				printf("%s: Unmerged\n",
+				       ce->name);
+			while (i < entries &&
+			       !strcmp(ce->name, active_cache[i]->name))
+				i++;
+			i--; /* compensate for loop control increments */
+			continue;
+		}
+ 
 		if (stat(ce->name, &st) < 0) {
-			printf("%s: %s\n", ce->name, strerror(errno));
-			if (errno == ENOENT && !silent)
-				show_diff_empty(ce);
+			if (errno == ENOENT && silent_on_nonexisting_files)
+				continue;
+			if (machine_readable)
+				printf("X %s%c", ce->name, 0);
+			else {
+				printf("%s: %s\n", ce->name, strerror(errno));
+				if (errno == ENOENT)
+					show_diff_empty(ce);
+			}
 			continue;
 		}
 		changed = cache_match_stat(ce, &st);
 		if (!changed)
 			continue;
-		printf("%.*s:  ", ce->namelen, ce->name);
-		for (n = 0; n < 20; n++)
-			printf("%02x", ce->sha1[n]);
-		printf("\n");
-		fflush(stdout);
+		if (!machine_readable)
+			printf("%s: %s\n", ce->name, sha1_to_hex(ce->sha1));
+		else {
+			printf("%s %s%c", sha1_to_hex(ce->sha1), ce->name, 0);
+			continue;
+		}
 		if (silent)
 			continue;
 
-		new = read_sha1_file(ce->sha1, type, &size);
-		show_differences(ce->name, new, size);
-		free(new);
+		old = read_sha1_file(ce->sha1, type, &size);
+		if (! old)
+			error("unable to read blob object for %s (%s)",
+			      ce->name, sha1_to_hex(ce->sha1));
+		else
+			show_differences(ce->name, ce->name, old, size);
+		free(old);
 	}
 	return 0;
 }