X-Git-Url: https://git.octo.it/?a=blobdiff_plain;f=receive-pack.c;h=d4e82bf99397d2e719e8bbe1e0e72142d04fb4cb;hb=e468305a954d95a26bfcdec3bc6e4bd477d95676;hp=601388314418349bf61e7de14d188b8fbb802aac;hpb=575f497456e4d4669b3b0095482ba2b86f6d2807;p=git.git

diff --git a/receive-pack.c b/receive-pack.c
index 60138831..d4e82bf9 100644
--- a/receive-pack.c
+++ b/receive-pack.c
@@ -1,208 +1,102 @@
 #include "cache.h"
+#include "refs.h"
+#include "pkt-line.h"
 #include <sys/wait.h>
 
-static const char receive_pack_usage[] = "git-receive-pack [--unpack=executable] <git-dir> [heads]";
+static const char receive_pack_usage[] = "git-receive-pack <git-dir>";
 
 static const char *unpacker = "git-unpack-objects";
 
-static int path_match(const char *path, int nr, char **match)
+static int show_ref(const char *path, const unsigned char *sha1)
 {
-	int i;
-	int pathlen = strlen(path);
-
-	for (i = 0; i < nr; i++) {
-		char *s = match[i];
-		int len = strlen(s);
-
-		if (!len || len > pathlen)
-			continue;
-		if (memcmp(path + pathlen - len, s, len))
-			continue;
-		if (pathlen > len && path[pathlen - len - 1] != '/')
-			continue;
-		*s = 0;
-		return 1;
-	}
+	packet_write(1, "%s %s\n", sha1_to_hex(sha1), path);
 	return 0;
 }
 
-static void safe_write(int fd, const void *buf, unsigned n)
+static void write_head_info(void)
 {
-	while (n) {
-		int ret = write(fd, buf, n);
-		if (ret > 0) {
-			buf += ret;
-			n -= ret;
-			continue;
-		}
-		if (!ret)
-			die("write error (disk full?)");
-		if (errno == EAGAIN || errno == EINTR)
-			continue;
-		die("write error (%s)", strerror(errno));
-	}
+	for_each_ref(show_ref);
 }
 
-/*
- * If we buffered things up above (we don't, but we should),
- * we'd flush it here
- */
-static void flush_safe(int fd)
-{
-}
-
-/*
- * Write a packetized stream, where each line is preceded by
- * its length (including the header) as a 4-byte hex number.
- * A length of 'zero' means end of stream (and a length of 1-3
- * would be an error). 
- */
-#define hex(a) (hexchar[(a) & 15])
-static void packet_write(const char *fmt, ...)
-{
-	static char buffer[1000];
-	static char hexchar[] = "0123456789abcdef";
-	va_list args;
-	unsigned n;
-
-	va_start(args, fmt);
-	n = vsnprintf(buffer + 4, sizeof(buffer) - 4, fmt, args);
-	va_end(args);
-	if (n >= sizeof(buffer)-4)
-		die("protocol error: impossibly long line");
-	n += 4;
-	buffer[0] = hex(n >> 12);
-	buffer[1] = hex(n >> 8);
-	buffer[2] = hex(n >> 4);
-	buffer[3] = hex(n);
-	safe_write(1, buffer, n);
-}
+struct command {
+	struct command *next;
+	unsigned char old_sha1[20];
+	unsigned char new_sha1[20];
+	char ref_name[0];
+};
 
-static void show_ref(const char *path, unsigned char *sha1)
-{
-	packet_write("%s %s\n", sha1_to_hex(sha1), path);
-}
+static struct command *commands = NULL;
 
-static int read_ref(const char *path, unsigned char *sha1)
+static int is_all_zeroes(const char *hex)
 {
-	int ret = -1;
-	int fd = open(path, O_RDONLY);
-
-	if (fd >= 0) {
-		char buffer[60];
-		if (read(fd, buffer, sizeof(buffer)) >= 40)
-			ret = get_sha1_hex(buffer, sha1);
-		close(fd);
-	}
-	return ret;
+	int i;
+	for (i = 0; i < 40; i++)
+		if (*hex++ != '0')
+			return 0;
+	return 1;
 }
 
-static void write_head_info(const char *base, int nr, char **match)
+static int verify_old_ref(const char *name, char *hex_contents)
 {
-	DIR *dir = opendir(base);
-
-	if (dir) {
-		struct dirent *de;
-		int baselen = strlen(base);
-		char *path = xmalloc(baselen + 257);
-		memcpy(path, base, baselen);
-
-		while ((de = readdir(dir)) != NULL) {
-			char sha1[20];
-			struct stat st;
-			int namelen;
+	int fd, ret;
+	char buffer[60];
 
-			if (de->d_name[0] == '.')
-				continue;
-			namelen = strlen(de->d_name);
-			if (namelen > 255)
-				continue;
-			memcpy(path + baselen, de->d_name, namelen+1);
-			if (lstat(path, &st) < 0)
-				continue;
-			if (S_ISDIR(st.st_mode)) {
-				path[baselen + namelen] = '/';
-				path[baselen + namelen + 1] = 0;
-				write_head_info(path, nr, match);
-				continue;
-			}
-			if (read_ref(path, sha1) < 0)
-				continue;
-			if (nr && !path_match(path, nr, match))
-				continue;
-			show_ref(path, sha1);
-		}
-		free(path);
-		closedir(dir);
-	}
+	if (is_all_zeroes(hex_contents))
+		return 0;
+	fd = open(name, O_RDONLY);
+	if (fd < 0)
+		return -1;
+	ret = read(fd, buffer, 40);
+	close(fd);
+	if (ret != 40)
+		return -1;
+	if (memcmp(buffer, hex_contents, 40))
+		return -1;
+	return 0;
 }
 
-/*
- * This is all pretty stupid, but we use this packetized line
- * format to make a streaming format possible without ever
- * over-running the read buffers. That way we'll never read
- * into what might be the pack data (which should go to another
- * process entirely).
- *
- * The writing side could use stdio, but since the reading
- * side can't, we stay with pure read/write interfaces.
- */
-static void safe_read(int fd, void *buffer, unsigned size)
+static void update(const char *name, unsigned char *old_sha1, unsigned char *new_sha1)
 {
-	int n = 0;
-
-	while (n < size) {
-		int ret = read(0, buffer + n, size - n);
-		if (ret < 0) {
-			if (errno == EINTR || errno == EAGAIN)
-				continue;
-			die("read error (%s)", strerror(errno));
-		}
-		if (!ret)
-			die("unexpected EOF");
-		n += ret;
+	char new_hex[60], *old_hex, *lock_name;
+	int newfd, namelen, written;
+
+	namelen = strlen(name);
+	lock_name = xmalloc(namelen + 10);
+	memcpy(lock_name, name, namelen);
+	memcpy(lock_name + namelen, ".lock", 6);
+
+	strcpy(new_hex, sha1_to_hex(new_sha1));
+	old_hex = sha1_to_hex(old_sha1);
+	if (!has_sha1_file(new_sha1))
+		die("unpack should have generated %s, but I can't find it!", new_hex);
+
+	newfd = open(lock_name, O_CREAT | O_EXCL | O_WRONLY, 0666);
+	if (newfd < 0)
+		die("unable to create %s (%s)", lock_name, strerror(errno));
+
+	/* Write the ref with an ending '\n' */
+	new_hex[40] = '\n';
+	new_hex[41] = 0;
+	written = write(newfd, new_hex, 41);
+	/* Remove the '\n' again */
+	new_hex[40] = 0;
+
+	close(newfd);
+	if (written != 41) {
+		unlink(lock_name);
+		die("unable to write %s", lock_name);
 	}
-}
-
-static int safe_read_line(char *buffer, unsigned size)
-{
-	int n, len;
-
-	safe_read(0, buffer, 4);
-
-	len = 0;
-	for (n = 0; n < 4; n++) {
-		unsigned char c = buffer[n];
-		len <<= 4;
-		if (c >= '0' && c <= '9') {
-			len += c - '0';
-			continue;
-		}
-		if (c >= 'a' && c <= 'f') {
-			len += c - 'a' + 10;
-			continue;
-		}
-		if (c >= 'A' && c <= 'F') {
-			len += c - 'A' + 10;
-			continue;
-		}
-		die("protocol error: bad line length character");
+	if (verify_old_ref(name, old_hex) < 0) {
+		unlink(lock_name);
+		die("%s changed during push", name);
 	}
-	if (!len)
-		return 0;
-	if (len < 4 || len >= size)
-		die("protocol error: bad line length %d", len);
-	safe_read(0, buffer + 4, len - 4);
-	buffer[len] = 0;
-	return len;
+	if (rename(lock_name, name) < 0) {
+		unlink(lock_name);
+		die("unable to replace %s", name);
+	}
+	fprintf(stderr, "%s: %s -> %s\n", name, old_hex, new_hex);
 }
 
-struct line {
-	struct line *next;
-	char data[0];
-};
-
-struct line *commands = NULL;
 
 /*
  * This gets called after(if) we've successfully
@@ -210,28 +104,42 @@ struct line *commands = NULL;
  */
 static void execute_commands(void)
 {
-	struct line *line = commands;
+	struct command *cmd = commands;
 
-	while (line) {
-		printf("%s", line->data);
-		line = line->next;
+	while (cmd) {
+		update(cmd->ref_name, cmd->old_sha1, cmd->new_sha1);
+		cmd = cmd->next;
 	}
+	update_server_info(0);
 }
 
 static void read_head_info(void)
 {
-	struct line **p = &commands;
+	struct command **p = &commands;
 	for (;;) {
 		static char line[1000];
-		int len = safe_read_line(line, sizeof(line));
-		struct line *n;
+		unsigned char old_sha1[20], new_sha1[20];
+		struct command *cmd;
+		int len;
+
+		len = packet_read_line(0, line, sizeof(line));
 		if (!len)
 			break;
-		n = xmalloc(sizeof(struct line) + len);
-		n->next = NULL;
-		memcpy(n->data, line + 4, len - 3);
-		*p = n;
-		p = &n->next;
+		if (line[len-1] == '\n')
+			line[--len] = 0;
+		if (len < 83 ||
+		    line[40] != ' ' ||
+		    line[81] != ' ' ||
+		    get_sha1_hex(line, old_sha1) ||
+		    get_sha1_hex(line + 41, new_sha1))
+			die("protocol error: expected old/new/ref, got '%s'", line);
+		cmd = xmalloc(sizeof(struct command) + len - 80);
+		memcpy(cmd->old_sha1, old_sha1, 20);
+		memcpy(cmd->new_sha1, new_sha1, 20);
+		memcpy(cmd->ref_name, line + 82, len - 81);
+		cmd->next = NULL;
+		*p = cmd;
+		p = &cmd->next;
 	}
 }
 
@@ -242,8 +150,7 @@ static void unpack(void)
 	if (pid < 0)
 		die("unpack fork failed");
 	if (!pid) {
-		char *const envp[] = { "GIT_DIR=.", NULL };
-		execle(unpacker, unpacker, NULL, envp);
+		execlp(unpacker, unpacker, NULL);
 		die("unpack execute failed");
 	}
 
@@ -271,51 +178,45 @@ static void unpack(void)
 
 int main(int argc, char **argv)
 {
-	int i, nr_heads = 0;
+	int i;
 	const char *dir = NULL;
-	char **heads = NULL;
 
 	argv++;
 	for (i = 1; i < argc; i++) {
 		const char *arg = *argv++;
 
 		if (*arg == '-') {
-			if (!strncmp(arg, "--unpack=", 9)) {
-				unpacker = arg+9;
-				continue;
-			}
 			/* Do flag handling here */
 			usage(receive_pack_usage);
 		}
+		if (dir)
+			usage(receive_pack_usage);
 		dir = arg;
-		heads = argv;
-		nr_heads = argc - i - 1;
-		break;
 	}
 	if (!dir)
 		usage(receive_pack_usage);
 
 	/* chdir to the directory. If that fails, try appending ".git" */
 	if (chdir(dir) < 0) {
-		static char path[PATH_MAX];
-		snprintf(path, sizeof(path), "%s.git", dir);
-		if (chdir(path) < 0)
+		if (chdir(mkpath("%s.git", dir)) < 0)
 			die("unable to cd to %s", dir);
 	}
 
 	/* If we have a ".git" directory, chdir to it */
 	chdir(".git");
+	setenv("GIT_DIR", ".", 1);
 
 	if (access("objects", X_OK) < 0 || access("refs/heads", X_OK) < 0)
 		die("%s doesn't appear to be a git directory", dir);
-	write_head_info("refs/", nr_heads, heads);
+	write_head_info();
 
 	/* EOF */
-	safe_write(1, "0000", 4);
-	flush_safe(1);
+	packet_flush(1);
 
 	read_head_info();
-	unpack();
-	execute_commands();
+	if (commands) {
+		unpack();
+		execute_commands();
+	}
 	return 0;
 }