X-Git-Url: https://git.verplant.org/?a=blobdiff_plain;f=read-cache.c;h=d8b383fe6b0544e65e9633f747346f8042f2840a;hb=42d545e8ff33f478a4b7b99562ab073d8820b334;hp=54536944648c166008f06d29f65314b58b0c3988;hpb=4bb04f2190d526f8917663f0be62d8026e1ed100;p=git.git

diff --git a/read-cache.c b/read-cache.c
index 54536944..d8b383fe 100644
--- a/read-cache.c
+++ b/read-cache.c
@@ -3,24 +3,47 @@
  *
  * Copyright (C) Linus Torvalds, 2005
  */
+#include <stdarg.h>
 #include "cache.h"
 
 const char *sha1_file_directory = NULL;
 struct cache_entry **active_cache = NULL;
 unsigned int active_nr = 0, active_alloc = 0;
 
-void usage(const char *err, ...)
+void usage(const char *err)
 {
-	va_list args;
-	char string[200];
+	fprintf(stderr, "usage: %s\n", err);
+	exit(1);
+}
+
+static void report(const char *prefix, const char *err, va_list params)
+{
+	fputs(prefix, stderr);
+	vfprintf(stderr, err, params);
+	fputs("\n", stderr);
+}
+
+void die(const char *err, ...)
+{
+	va_list params;
 
-	va_start(args, err);
-	vsnprintf(string, sizeof(string), err, args);
-	va_end(args);
-	fprintf(stderr, "%s\n", string);
+	va_start(params, err);
+	report("fatal: ", err, params);
+	va_end(params);
 	exit(1);
 }
 
+int error(const char *err, ...)
+{
+	va_list params;
+
+	va_start(params, err);
+	report("error: ", err, params);
+	va_end(params);
+	return -1;
+}
+
+
 static unsigned hexval(char c)
 {
 	if (c >= '0' && c <= '9')
@@ -216,28 +239,47 @@ int write_sha1_buffer(const unsigned char *sha1, void *buf, unsigned int size)
 	int fd;
 
 	fd = open(filename, O_WRONLY | O_CREAT | O_EXCL, 0666);
-	if (fd < 0)
-		return (errno == EEXIST) ? 0 : -1;
+	if (fd < 0) {
+		void *map;
+
+		if (errno != EEXIST)
+			return -1;
+#ifndef COLLISION_CHECK
+		fd = open(filename, O_RDONLY);
+		if (fd < 0)
+			return -1;
+		map = mmap(NULL, size, PROT_READ, MAP_PRIVATE, fd, 0);
+		if (map == MAP_FAILED)
+			return -1;
+		if (memcmp(buf, map, size))
+			return error("SHA1 collision detected!"
+					" This is bad, bad, BAD!\a\n");
+#endif
+		return 0;
+	}
 	write(fd, buf, size);
 	close(fd);
 	return 0;
 }
 
-static int error(const char * string)
-{
-	fprintf(stderr, "error: %s\n", string);
-	return -1;
-}
-
 int cache_match_stat(struct cache_entry *ce, struct stat *st)
 {
 	unsigned int changed = 0;
 
-	if (ce->mtime.sec  != (unsigned int)st->st_mtim.tv_sec ||
-	    ce->mtime.nsec != (unsigned int)st->st_mtim.tv_nsec)
+	/* nsec seems unreliable - not all filesystems support it, so
+	 * as long as it is in the inode cache you get right nsec
+	 * but after it gets flushed, you get zero nsec. */
+	if (ce->mtime.sec  != (unsigned int)st->st_mtim.tv_sec
+#ifdef NSEC
+	    || ce->mtime.nsec != (unsigned int)st->st_mtim.tv_nsec
+#endif
+	    )
 		changed |= MTIME_CHANGED;
-	if (ce->ctime.sec  != (unsigned int)st->st_ctim.tv_sec ||
-	    ce->ctime.nsec != (unsigned int)st->st_ctim.tv_nsec)
+	if (ce->ctime.sec  != (unsigned int)st->st_ctim.tv_sec
+#ifdef NSEC
+	    || ce->ctime.nsec != (unsigned int)st->st_ctim.tv_nsec
+#endif
+	    )
 		changed |= CTIME_CHANGED;
 	if (ce->st_uid != (unsigned int)st->st_uid ||
 	    ce->st_gid != (unsigned int)st->st_gid)