X-Git-Url: https://git.verplant.org/?a=blobdiff_plain;f=show-diff.c;h=2ff0bd4ea636db2ad54e9ff34e1d70ac7a9a98f0;hb=bfac5d94291bdb951ae3e739598a32bf868ea806;hp=d9af29fd876612855dfe659f6bb270804118edef;hpb=734aab758cc2b9f5e2ed43375dbfec1b5bfde43b;p=git.git

diff --git a/show-diff.c b/show-diff.c
index d9af29fd..2ff0bd4e 100644
--- a/show-diff.c
+++ b/show-diff.c
@@ -5,51 +5,208 @@
  */
 #include "cache.h"
 
-static void show_differences(struct cache_entry *ce, struct stat *cur,
-	void *old_contents, unsigned long long old_size)
+static char *diff_cmd = "diff -L 'a/%s' -L 'b/%s' ";
+static char *diff_opts = "-p -u";
+static char *diff_arg_forward  = " - '%s'";
+static char *diff_arg_reverse  = " '%s' -";
+
+static void prepare_diff_cmd(void)
+{
+	/*
+	 * Default values above are meant to match the
+	 * Linux kernel development style.  Examples of
+	 * alternative styles you can specify via environment
+	 * variables are:
+	 *
+	 * GIT_DIFF_CMD="diff -L '%s' -L '%s'"
+	 * GIT_DIFF_OPTS="-c";
+	 */
+	diff_cmd = getenv("GIT_DIFF_CMD") ? : diff_cmd;
+	diff_opts = getenv("GIT_DIFF_OPTS") ? : diff_opts;
+}
+
+/* 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'
+ */
+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, int reverse)
 {
-	static char cmd[1000];
 	FILE *f;
+	char *name_sq = sq_expand(name);
+	char *label_sq = (name != label) ? sq_expand(label) : name_sq;
+	char *diff_arg = reverse ? diff_arg_reverse : diff_arg_forward;
+	int cmd_size = strlen(name_sq) + strlen(label_sq) * 2 +
+		strlen(diff_cmd) + strlen(diff_opts) + strlen(diff_arg);
+	char *cmd = malloc(cmd_size);
+	int next_at;
 
-	snprintf(cmd, sizeof(cmd), "diff -u - %s", ce->name);
+	fflush(stdout);
+	next_at = snprintf(cmd, cmd_size, diff_cmd, label_sq, label_sq);
+	next_at += snprintf(cmd+next_at, cmd_size-next_at, "%s", diff_opts);
+	next_at += snprintf(cmd+next_at, cmd_size-next_at, diff_arg, name_sq);
 	f = popen(cmd, "w");
-	fwrite(old_contents, old_size, 1, f);
+	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, int reverse)
+{
+	char *old;
+	unsigned long int size;
+	unsigned char type[20];
+
+	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));
+		return;
+	}
+	show_differences("/dev/null", ce->name, old, size, reverse);
+}
+
+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 reverse = 0;
 	int entries = read_cache();
 	int i;
 
+	while (1 < argc && argv[1][0] == '-') {
+		if  (!strcmp(argv[1], "-R"))
+			reverse = 1;
+		else 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);
 	}
+	prepare_diff_cmd();
 	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_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, reverse);
+			}
 			continue;
 		}
 		changed = cache_match_stat(ce, &st);
-		if (!changed) {
-			printf("%s: ok\n", ce->name);
+		if (!changed)
+			continue;
+		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;
 		}
-		printf("%.*s:  ", ce->namelen, ce->name);
-		for (n = 0; n < 20; n++)
-			printf("%02x", ce->sha1[n]);
-		printf("\n");
-		new = read_sha1_file(ce->sha1, type, &size);
-		show_differences(ce, &st, new, size);
-		free(new);
+		if (silent)
+			continue;
+
+		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,
+					 reverse);
+		free(old);
 	}
 	return 0;
 }