X-Git-Url: https://git.verplant.org/?a=blobdiff_plain;f=diff.c;h=65110333f2a71b0f4ff13094b431380089b79ffe;hb=c983370e5e208cca4deda82184478ba445a156e6;hp=c064e10580d5e1f7185f3f32ee19319292f6b43d;hpb=2f97813870c73a89b673ea7882f2a078d25c2dcd;p=git.git

diff --git a/diff.c b/diff.c
index c064e105..65110333 100644
--- a/diff.c
+++ b/diff.c
@@ -3,6 +3,7 @@
  */
 #include <sys/types.h>
 #include <sys/wait.h>
+#include <signal.h>
 #include "cache.h"
 #include "diff.h"
 
@@ -81,35 +82,32 @@ static void builtin_diff(const char *name,
 			 struct diff_tempfile *temp)
 {
 	int i, next_at;
-	const char *diff_cmd = "diff -L'%s%s%s' -L'%s%s%s'";
+	const char *diff_cmd = "diff -L'%s%s' -L'%s%s'";
 	const char *diff_arg  = "'%s' '%s'";
 	const char *input_name_sq[2];
 	const char *path0[2];
 	const char *path1[2];
-	char mode[2][20];
 	const char *name_sq = sq_expand(name);
 	char *cmd;
 	
-	/* diff_cmd and diff_arg have 8 %s in total which makes
-	 * the sum of these strings 16 bytes larger than required.
+	/* diff_cmd and diff_arg have 6 %s in total which makes
+	 * the sum of these strings 12 bytes larger than required.
 	 * we use 2 spaces around diff-opts, and we need to count
-	 * terminating NUL, so we subtract 13 here.
+	 * terminating NUL, so we subtract 9 here.
 	 */
 	int cmd_size = (strlen(diff_cmd) + strlen(diff_opts) +
-			strlen(diff_arg) - 13);
+			strlen(diff_arg) - 9);
 	for (i = 0; i < 2; i++) {
 		input_name_sq[i] = sq_expand(temp[i].name);
 		if (!strcmp(temp[i].name, "/dev/null")) {
 			path0[i] = "/dev/null";
 			path1[i] = "";
-			mode[i][0] = 0;
 		} else {
 			path0[i] = i ? "l/" : "k/";
 			path1[i] = name_sq;
-			sprintf(mode[i], "  (mode:%s)", temp[i].mode);
 		}
 		cmd_size += (strlen(path0[i]) + strlen(path1[i]) +
-			     strlen(mode[i]) + strlen(input_name_sq[i]));
+			     strlen(input_name_sq[i]));
 	}
 
 	cmd = xmalloc(cmd_size);
@@ -117,13 +115,20 @@ static void builtin_diff(const char *name,
 	next_at = 0;
 	next_at += snprintf(cmd+next_at, cmd_size-next_at,
 			    diff_cmd,
-			    path0[0], path1[0], mode[0],
-			    path0[1], path1[1], mode[1]);
+			    path0[0], path1[0], path0[1], path1[1]);
 	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, input_name_sq[0], input_name_sq[1]);
 
+	if (!path1[0][0])
+		printf("Created: %s (mode:%s)\n", name, temp[1].mode);
+	else if (!path1[1][0])
+		printf("Deleted: %s\n", name);
+	else if (strcmp(temp[0].mode, temp[1].mode))
+		printf("Mode changed: %s (%s->%s)\n", name,
+		       temp[0].mode, temp[1].mode);
+	fflush(NULL);
 	execlp("/bin/sh","sh", "-c", cmd, NULL);
 }
 
@@ -135,6 +140,9 @@ static void prepare_temp_file(const char *name,
 
 	if (!one->file_valid) {
 	not_a_valid_file:
+		/* A '-' entry produces this for file-2, and
+		 * a '+' entry produces this for file-1.
+		 */
 		temp->name = "/dev/null";
 		strcpy(temp->hex, ".");
 		strcpy(temp->mode, ".");
@@ -155,7 +163,7 @@ static void prepare_temp_file(const char *name,
 				goto not_a_valid_file;
 			die("stat(%s): %s", temp->name, strerror(errno));
 		}
-		strcpy(temp->hex, ".");
+		strcpy(temp->hex, sha1_to_hex(null_sha1));
 		sprintf(temp->mode, "%06o",
 			S_IFREG |ce_permissions(st.st_mode));
 	}
@@ -196,6 +204,11 @@ static void remove_tempfile(void)
 		}
 }
 
+static void remove_tempfile_on_signal(int signo)
+{
+	remove_tempfile();
+}
+
 /* An external diff command takes:
  *
  * diff-cmd name infile1 infile1-sha1 infile1-mode \
@@ -207,7 +220,8 @@ void run_external_diff(const char *name,
 		       struct diff_spec *two)
 {
 	struct diff_tempfile *temp = diff_temp;
-	int pid, status;
+	pid_t pid;
+	int status;
 	static int atexit_asked = 0;
 
 	if (one && two) {
@@ -219,6 +233,7 @@ void run_external_diff(const char *name,
 			atexit_asked = 1;
 			atexit(remove_tempfile);
 		}
+		signal(SIGINT, remove_tempfile_on_signal);
 	}
 
 	fflush(NULL);
@@ -246,9 +261,17 @@ void run_external_diff(const char *name,
 			printf("* Unmerged path %s\n", name);
 		exit(0);
 	}
-	if (waitpid(pid, &status, 0) < 0 || !WIFEXITED(status))
-		die("diff program failed");
-
+	if (waitpid(pid, &status, 0) < 0 || !WIFEXITED(status)) {
+		/* We do not check the exit status because typically
+		 * diff exits non-zero if files are different, and
+		 * we are not interested in knowing that.  We *knew*
+		 * they are different and that's why we ran diff
+		 * in the first place!  However if it dies by a signal,
+		 * we stop processing immediately.
+		 */
+		remove_tempfile();
+		die("external diff died unexpectedly.\n");
+	}
 	remove_tempfile();
 }