X-Git-Url: https://git.tokkee.org/?a=blobdiff_plain;ds=sidebyside;f=sha1_file.c;h=e1ee0ad349497d6470bc00aa7f1085d9d1b83b43;hb=35ad33823e90fb166a6480cdc9195051535e9788;hp=eee3598bb75e2199045b823f007e7933c0fb9cfe;hpb=706bc531a19f268bb03dda7551929dee20172548;p=git.git

diff --git a/sha1_file.c b/sha1_file.c
index eee3598bb..e1ee0ad34 100644
--- a/sha1_file.c
+++ b/sha1_file.c
@@ -11,6 +11,16 @@
 
 const char *sha1_file_directory = NULL;
 
+#ifndef O_NOATIME
+#if defined(__linux__) && (defined(__i386__) || defined(__PPC__))
+#define O_NOATIME 01000000
+#else
+#define O_NOATIME 0
+#endif
+#endif
+
+static unsigned int sha1_file_open_flag = O_NOATIME;
+
 static unsigned hexval(char c)
 {
 	if (c >= '0' && c <= '9')
@@ -35,6 +45,92 @@ int get_sha1_hex(const char *hex, unsigned char *sha1)
 	return 0;
 }
 
+int get_sha1_file(const char *path, unsigned char *result)
+{
+	char buffer[60];
+	int fd = open(path, O_RDONLY);
+	int len;
+
+	if (fd < 0)
+		return -1;
+	len = read(fd, buffer, sizeof(buffer));
+	close(fd);
+	if (len < 40)
+		return -1;
+	return get_sha1_hex(buffer, result);
+}
+
+static int get_parent(int index, const char *str, unsigned char *result)
+{
+	unsigned char sha1[20];
+	char *buffer;
+	unsigned long size, offset;
+	int ret;
+
+	if (get_sha1(str, sha1) < 0)
+		return -1;
+	buffer = read_object_with_reference(sha1, "commit", &size, NULL);
+	if (!buffer)
+		return -1;
+	ret = -1;
+	offset = 46;
+	for (;;) {
+		if (offset + 48 > size)
+			break;
+		if (memcmp(buffer + offset, "parent ", 7))
+			break;
+		if (index > 0) {
+			offset += 48;
+			index--;
+			continue;
+		}
+		ret = get_sha1_hex(buffer + offset + 7, result);
+		break;
+	}
+	free(buffer);
+	return ret;	
+}
+
+int get_sha1(const char *str, unsigned char *sha1)
+{
+	static char pathname[PATH_MAX];
+	static const char *prefix[] = {
+		"",
+		"refs",
+		"refs/tags",
+		"refs/heads",
+		"refs/snap",
+		NULL
+	};
+	const char *gitdir;
+	const char **p;
+
+	if (!get_sha1_hex(str, sha1))
+		return 0;
+
+	switch (*str) {
+	case '/':
+		if (!get_sha1_file(str, sha1))
+			return 0;
+		break;
+	case '-':
+		return get_parent(0, str+1, sha1);
+	case '0' ... '9':
+		if (str[1] == '-')
+			return get_parent(*str - '0', str+2, sha1);
+		break;
+	}
+
+	gitdir = ".git";
+	for (p = prefix; *p; p++) {
+		snprintf(pathname, sizeof(pathname), "%s/%s/%s", gitdir, *p, str);
+		if (!get_sha1_file(pathname, sha1))
+			return 0;
+	}
+
+	return -1;
+}
+
 char * sha1_to_hex(const unsigned char *sha1)
 {
 	static char buffer[50];
@@ -63,7 +159,7 @@ char *sha1_file_name(const unsigned char *sha1)
 	if (!base) {
 		char *sha1_file_directory = getenv(DB_ENVIRONMENT) ? : DEFAULT_DB_ENVIRONMENT;
 		int len = strlen(sha1_file_directory);
-		base = malloc(len + 60);
+		base = xmalloc(len + 60);
 		memcpy(base, sha1_file_directory, len);
 		memset(base+len, 0, 60);
 		base[len] = '/';
@@ -96,13 +192,26 @@ int check_sha1_signature(unsigned char *sha1, void *map, unsigned long size, con
 void *map_sha1_file(const unsigned char *sha1, unsigned long *size)
 {
 	char *filename = sha1_file_name(sha1);
-	int fd = open(filename, O_RDONLY);
 	struct stat st;
 	void *map;
+	int fd;
 
+	fd = open(filename, O_RDONLY | sha1_file_open_flag);
 	if (fd < 0) {
-		perror(filename);
-		return NULL;
+		/* See if it works without O_NOATIME */
+		switch (sha1_file_open_flag) {
+		default:
+			fd = open(filename, O_RDONLY);
+			if (fd >= 0)
+				break;
+		/* Fallthrough */
+		case 0:
+			perror(filename);
+			return NULL;
+		}
+
+		/* If it failed once, it will probably fail again. Stop using O_NOATIME */
+		sha1_file_open_flag = 0;
 	}
 	if (fstat(fd, &st) < 0) {
 		close(fd);
@@ -132,13 +241,13 @@ void * unpack_sha1_file(void *map, unsigned long mapsize, char *type, unsigned l
 
 	inflateInit(&stream);
 	ret = inflate(&stream, 0);
+	if (ret < Z_OK)
+		return NULL;
 	if (sscanf(buffer, "%10s %lu", type, size) != 2)
 		return NULL;
 
 	bytes = strlen(buffer) + 1;
-	buf = malloc(*size);
-	if (!buf)
-		return NULL;
+	buf = xmalloc(*size);
 
 	memcpy(buf, buffer + bytes, stream.total_out - bytes);
 	bytes = stream.total_out - bytes;
@@ -166,7 +275,52 @@ void * read_sha1_file(const unsigned char *sha1, char *type, unsigned long *size
 	return NULL;
 }
 
-int write_sha1_file(char *buf, unsigned len, unsigned char *returnsha1)
+void *read_object_with_reference(const unsigned char *sha1,
+				 const unsigned char *required_type,
+				 unsigned long *size,
+				 unsigned char *actual_sha1_return)
+{
+	char type[20];
+	void *buffer;
+	unsigned long isize;
+	unsigned char actual_sha1[20];
+
+	memcpy(actual_sha1, sha1, 20);
+	while (1) {
+		int ref_length = -1;
+		const char *ref_type = NULL;
+
+		buffer = read_sha1_file(actual_sha1, type, &isize);
+		if (!buffer)
+			return NULL;
+		if (!strcmp(type, required_type)) {
+			*size = isize;
+			if (actual_sha1_return)
+				memcpy(actual_sha1_return, actual_sha1, 20);
+			return buffer;
+		}
+		/* Handle references */
+		else if (!strcmp(type, "commit"))
+			ref_type = "tree ";
+		else if (!strcmp(type, "tag"))
+			ref_type = "object ";
+		else {
+			free(buffer);
+			return NULL;
+		}
+		ref_length = strlen(ref_type);
+
+		if (memcmp(buffer, ref_type, ref_length) ||
+		    get_sha1_hex(buffer + ref_length, actual_sha1)) {
+			free(buffer);
+			return NULL;
+		}
+		/* Now we have the ID of the referred-to object in
+		 * actual_sha1.  Check again. */
+	}
+}
+
+int write_sha1_file(char *buf, unsigned long len, const char *type, unsigned char *returnsha1)
 {
 	int size;
 	char *compressed;
@@ -174,10 +328,15 @@ int write_sha1_file(char *buf, unsigned len, unsigned char *returnsha1)
 	unsigned char sha1[20];
 	SHA_CTX c;
 	char *filename;
-	int fd;
+	char hdr[50];
+	int fd, hdrlen;
+
+	/* Generate the header */
+	hdrlen = sprintf(hdr, "%s %lu", type, len)+1;
 
 	/* Sha1.. */
 	SHA1_Init(&c);
+	SHA1_Update(&c, hdr, hdrlen);
 	SHA1_Update(&c, buf, len);
 	SHA1_Final(sha1, &c);
 
@@ -200,14 +359,22 @@ int write_sha1_file(char *buf, unsigned len, unsigned char *returnsha1)
 	/* Set it up */
 	memset(&stream, 0, sizeof(stream));
 	deflateInit(&stream, Z_BEST_COMPRESSION);
-	size = deflateBound(&stream, len);
-	compressed = malloc(size);
+	size = deflateBound(&stream, len+hdrlen);
+	compressed = xmalloc(size);
 
 	/* Compress it */
-	stream.next_in = buf;
-	stream.avail_in = len;
 	stream.next_out = compressed;
 	stream.avail_out = size;
+
+	/* First header.. */
+	stream.next_in = hdr;
+	stream.avail_in = hdrlen;
+	while (deflate(&stream, 0) == Z_OK)
+		/* nothing */
+
+	/* Then the data itself.. */
+	stream.next_in = buf;
+	stream.avail_in = len;
 	while (deflate(&stream, Z_FINISH) == Z_OK)
 		/* nothing */;
 	deflateEnd(&stream);
@@ -265,3 +432,75 @@ int write_sha1_buffer(const unsigned char *sha1, void *buf, unsigned int size)
 	close(fd);
 	return 0;
 }
+
+int write_sha1_from_fd(const unsigned char *sha1, int fd)
+{
+	char *filename = sha1_file_name(sha1);
+
+	int local;
+	z_stream stream;
+	unsigned char real_sha1[20];
+	char buf[4096];
+	char discard[4096];
+	int ret;
+	SHA_CTX c;
+
+	local = open(filename, O_WRONLY | O_CREAT | O_EXCL, 0666);
+
+	if (local < 0)
+		return error("Couldn't open %s\n", filename);
+
+	memset(&stream, 0, sizeof(stream));
+
+	inflateInit(&stream);
+
+	SHA1_Init(&c);
+
+	do {
+		ssize_t size;
+		size = read(fd, buf, 4096);
+		if (size <= 0) {
+			close(local);
+			unlink(filename);
+			if (!size)
+				return error("Connection closed?");
+			perror("Reading from connection");
+			return -1;
+		}
+		write(local, buf, size);
+		stream.avail_in = size;
+		stream.next_in = buf;
+		do {
+			stream.next_out = discard;
+			stream.avail_out = sizeof(discard);
+			ret = inflate(&stream, Z_SYNC_FLUSH);
+			SHA1_Update(&c, discard, sizeof(discard) -
+				    stream.avail_out);
+		} while (stream.avail_in && ret == Z_OK);
+		
+	} while (ret == Z_OK);
+	inflateEnd(&stream);
+
+	close(local);
+	SHA1_Final(real_sha1, &c);
+	if (ret != Z_STREAM_END) {
+		unlink(filename);
+		return error("File %s corrupted", sha1_to_hex(sha1));
+	}
+	if (memcmp(sha1, real_sha1, 20)) {
+		unlink(filename);
+		return error("File %s has bad hash\n", sha1_to_hex(sha1));
+	}
+	
+	return 0;
+}
+
+int has_sha1_file(const unsigned char *sha1)
+{
+	char *filename = sha1_file_name(sha1);
+	struct stat st;
+
+	if (!stat(filename, &st))
+		return 1;
+	return 0;
+}