X-Git-Url: https://git.octo.it/?a=blobdiff_plain;f=tar-tree.c;h=2be42fe6cbbf2ac835ba08ec7a091005fad8315f;hb=cb0c6df6f5e850875af28b47c5c94482a326293f;hp=2c64f690e52093af13585521de4df478ac6e85e5;hpb=3c249c950649a37f2871a8b193f01a0640a20aef;p=git.git

diff --git a/tar-tree.c b/tar-tree.c
index 2c64f690..2be42fe6 100644
--- a/tar-tree.c
+++ b/tar-tree.c
@@ -1,10 +1,20 @@
+/*
+ * Copyright (c) 2005, 2006 Rene Scharfe
+ */
 #include <time.h>
 #include "cache.h"
+#include "diff.h"
+#include "commit.h"
+#include "strbuf.h"
+#include "tar.h"
 
 #define RECORDSIZE	(512)
 #define BLOCKSIZE	(RECORDSIZE * 20)
 
-static const char *tar_tree_usage = "tar-tree <key> [basedir]";
+#define EXT_HEADER_PATH		1
+#define EXT_HEADER_LINKPATH	2
+
+static const char tar_tree_usage[] = "git-tar-tree <key> [basedir]";
 
 static char block[BLOCKSIZE];
 static unsigned long offset;
@@ -21,15 +31,13 @@ struct path_prefix {
 static void reliable_write(void *buf, unsigned long size)
 {
 	while (size > 0) {
-		long ret = write(1, buf, size);
+		long ret = xwrite(1, buf, size);
 		if (ret < 0) {
-			if (errno == EAGAIN)
-				continue;
 			if (errno == EPIPE)
 				exit(0);
-			die("tar-tree: %s", strerror(errno));
+			die("git-tar-tree: %s", strerror(errno));
 		} else if (!ret) {
-			die("tar-tree: disk full?");
+			die("git-tar-tree: disk full?");
 		}
 		size -= ret;
 		buf += ret;
@@ -45,22 +53,28 @@ static void write_if_needed(void)
 	}
 }
 
+/* acquire the next record from the buffer; user must call write_if_needed() */
+static char *get_record(void)
+{
+	char *p = block + offset;
+	memset(p, 0, RECORDSIZE);
+	offset += RECORDSIZE;
+	return p;
+}
+
 /*
  * The end of tar archives is marked by 1024 nul bytes and after that
  * follows the rest of the block (if any).
  */
 static void write_trailer(void)
 {
-	memset(block + offset, 0, RECORDSIZE);
-	offset += RECORDSIZE;
+	get_record();
 	write_if_needed();
-	memset(block + offset, 0, RECORDSIZE);
-	offset += RECORDSIZE;
+	get_record();
 	write_if_needed();
-	if (offset) {
-		memset(block + offset, 0, BLOCKSIZE - offset);
-		reliable_write(block, BLOCKSIZE);
-		offset = 0;
+	while (offset) {
+		get_record();
+		write_if_needed();
 	}
 }
 
@@ -100,6 +114,139 @@ static void write_blocked(void *buf, unsigned long size)
 	write_if_needed();
 }
 
+static void strbuf_append_string(struct strbuf *sb, const char *s)
+{
+	int slen = strlen(s);
+	int total = sb->len + slen;
+	if (total > sb->alloc) {
+		sb->buf = xrealloc(sb->buf, total);
+		sb->alloc = total;
+	}
+	memcpy(sb->buf + sb->len, s, slen);
+	sb->len = total;
+}
+
+/*
+ * pax extended header records have the format "%u %s=%s\n".  %u contains
+ * the size of the whole string (including the %u), the first %s is the
+ * keyword, the second one is the value.  This function constructs such a
+ * string and appends it to a struct strbuf.
+ */
+static void strbuf_append_ext_header(struct strbuf *sb, const char *keyword,
+                                     const char *value, unsigned int valuelen)
+{
+	char *p;
+	int len, total, tmp;
+
+	/* "%u %s=%s\n" */
+	len = 1 + 1 + strlen(keyword) + 1 + valuelen + 1;
+	for (tmp = len; tmp > 9; tmp /= 10)
+		len++;
+
+	total = sb->len + len;
+	if (total > sb->alloc) {
+		sb->buf = xrealloc(sb->buf, total);
+		sb->alloc = total;
+	}
+
+	p = sb->buf;
+	p += sprintf(p, "%u %s=", len, keyword);
+	memcpy(p, value, valuelen);
+	p += valuelen;
+	*p = '\n';
+	sb->len = total;
+}
+
+static unsigned int ustar_header_chksum(const struct ustar_header *header)
+{
+	char *p = (char *)header;
+	unsigned int chksum = 0;
+	while (p < header->chksum)
+		chksum += *p++;
+	chksum += sizeof(header->chksum) * ' ';
+	p += sizeof(header->chksum);
+	while (p < (char *)header + sizeof(struct ustar_header))
+		chksum += *p++;
+	return chksum;
+}
+
+static void write_entry(const unsigned char *sha1, struct strbuf *path,
+                        unsigned int mode, void *buffer, unsigned long size)
+{
+	struct ustar_header header;
+	struct strbuf ext_header;
+
+	memset(&header, 0, sizeof(header));
+	ext_header.buf = NULL;
+	ext_header.len = ext_header.alloc = 0;
+
+	if (!sha1) {
+		*header.typeflag = TYPEFLAG_GLOBAL_HEADER;
+		mode = 0100666;
+		strcpy(header.name, "pax_global_header");
+	} else if (!path) {
+		*header.typeflag = TYPEFLAG_EXT_HEADER;
+		mode = 0100666;
+		sprintf(header.name, "%s.paxheader", sha1_to_hex(sha1));
+	} else {
+		if (S_ISDIR(mode)) {
+			*header.typeflag = TYPEFLAG_DIR;
+			mode |= 0777;
+		} else if (S_ISLNK(mode)) {
+			*header.typeflag = TYPEFLAG_LNK;
+			mode |= 0777;
+		} else if (S_ISREG(mode)) {
+			*header.typeflag = TYPEFLAG_REG;
+			mode |= (mode & 0100) ? 0777 : 0666;
+		} else {
+			error("unsupported file mode: 0%o (SHA1: %s)",
+			      mode, sha1_to_hex(sha1));
+			return;
+		}
+		if (path->len > sizeof(header.name)) {
+			sprintf(header.name, "%s.data", sha1_to_hex(sha1));
+			strbuf_append_ext_header(&ext_header, "path",
+				                 path->buf, path->len);
+		} else
+			memcpy(header.name, path->buf, path->len);
+	}
+
+	if (S_ISLNK(mode) && buffer) {
+		if (size > sizeof(header.linkname)) {
+			sprintf(header.linkname, "see %s.paxheader",
+			        sha1_to_hex(sha1));
+			strbuf_append_ext_header(&ext_header, "linkpath",
+			                         buffer, size);
+		} else
+			memcpy(header.linkname, buffer, size);
+	}
+
+	sprintf(header.mode, "%07o", mode & 07777);
+	sprintf(header.size, "%011lo", S_ISREG(mode) ? size : 0);
+	sprintf(header.mtime, "%011lo", archive_time);
+
+	/* XXX: should we provide more meaningful info here? */
+	sprintf(header.uid, "%07o", 0);
+	sprintf(header.gid, "%07o", 0);
+	strncpy(header.uname, "git", 31);
+	strncpy(header.gname, "git", 31);
+	sprintf(header.devmajor, "%07o", 0);
+	sprintf(header.devminor, "%07o", 0);
+
+	memcpy(header.magic, "ustar", 6);
+	memcpy(header.version, "00", 2);
+
+	sprintf(header.chksum, "%07o", ustar_header_chksum(&header));
+
+	if (ext_header.len > 0) {
+		write_entry(sha1, NULL, 0, ext_header.buf, ext_header.len);
+		free(ext_header.buf);
+	}
+	write_blocked(&header, sizeof(header));
+	if (S_ISREG(mode) && buffer && size > 0)
+		write_blocked(buffer, size);
+}
+
 static void append_string(char **p, const char *s)
 {
 	unsigned int len = strlen(s);
@@ -113,12 +260,6 @@ static void append_char(char **p, char c)
 	*p += 1;
 }
 
-static void append_long(char **p, long n)
-{
-	int len = sprintf(*p, "%ld", n);
-	*p += len;
-}
-
 static void append_path_prefix(char **buffer, struct path_prefix *prefix)
 {
 	if (!prefix)
@@ -160,83 +301,138 @@ static unsigned int path_len(int is_dir, const char *basepath,
 	return len;
 }
 
-static void write_header(const char *, char, const char *, struct path_prefix *,
-                         const char *, unsigned int, unsigned long);
+static void append_extended_header_prefix(char **p, unsigned int size,
+                                          const char *keyword)
+{
+	int len = sprintf(*p, "%u %s=", size, keyword);
+	*p += len;
+}
+
+static unsigned int extended_header_len(const char *keyword,
+                                        unsigned int valuelen)
+{
+	/* "%u %s=%s\n" */
+	unsigned int len = 1 + 1 + strlen(keyword) + 1 + valuelen + 1;
+	if (len > 9)
+		len++;
+	if (len > 99)
+		len++;
+	return len;
+}
+
+static void append_extended_header(char **p, const char *keyword,
+                                   const char *value, unsigned int len)
+{
+	unsigned int size = extended_header_len(keyword, len);
+	append_extended_header_prefix(p, size, keyword);
+	memcpy(*p, value, len);
+	*p += len;
+	append_char(p, '\n');
+}
+
+static void write_header(const unsigned char *, char, const char *, struct path_prefix *,
+                         const char *, unsigned int, void *, unsigned long);
 
 /* stores a pax extended header directly in the block buffer */
 static void write_extended_header(const char *headerfilename, int is_dir,
-                                  const char *basepath,
+                                  unsigned int flags, const char *basepath,
                                   struct path_prefix *prefix,
-                                  const char *path, unsigned int namelen)
+                                  const char *path, unsigned int namelen,
+                                  void *content, unsigned int contentsize)
 {
-	char *p;
-	unsigned int size = 1 + 6 + namelen + 1;
-	if (size > 9)
-		size++;
-	if (size > 99)
-		size++;
-	if (size > RECORDSIZE)
-		die("tar-tree: extended header too big, wtf?");
-	write_header(NULL, 'x', NULL, NULL, headerfilename, 0100600, size);
-	p = block + offset;
-	memset(p, 0, RECORDSIZE);
-	offset += RECORDSIZE;
-	append_long(&p, size);
-	append_string(&p, " path=");
+	char *buffer, *p;
+	unsigned int pathlen, size, linkpathlen = 0;
+
+	size = pathlen = extended_header_len("path", namelen);
+	if (flags & EXT_HEADER_LINKPATH) {
+		linkpathlen = extended_header_len("linkpath", contentsize);
+		size += linkpathlen;
+	}
+	write_header(NULL, TYPEFLAG_EXT_HEADER, NULL, NULL, headerfilename,
+	             0100600, NULL, size);
+
+	buffer = p = malloc(size);
+	if (!buffer)
+		die("git-tar-tree: %s", strerror(errno));
+	append_extended_header_prefix(&p, pathlen, "path");
 	append_path(&p, is_dir, basepath, prefix, path);
 	append_char(&p, '\n');
-	write_if_needed();
+	if (flags & EXT_HEADER_LINKPATH)
+		append_extended_header(&p, "linkpath", content, contentsize);
+	write_blocked(buffer, size);
+	free(buffer);
 }
 
-static void write_global_extended_header(const char *sha1)
+static void write_global_extended_header(const unsigned char *sha1)
 {
-	char *p;
-	write_header(NULL, 'g', NULL, NULL, "pax_global_header", 0, 52);
-	p = block + offset;
-	memset(p, 0, RECORDSIZE);
-	offset += RECORDSIZE;
-	append_long(&p, 52);	/* 2 + 9 + 40 + 1 */
-	append_string(&p, " comment=");
-	append_string(&p, sha1_to_hex(sha1));
-	append_char(&p, '\n');
-	write_if_needed();
+	struct strbuf ext_header;
+	ext_header.buf = NULL;
+	ext_header.len = ext_header.alloc = 0;
+	strbuf_append_ext_header(&ext_header, "comment", sha1_to_hex(sha1), 40);
+	write_entry(NULL, NULL, 0, ext_header.buf, ext_header.len);
+	free(ext_header.buf);
 }
 
 /* stores a ustar header directly in the block buffer */
-static void write_header(const char *sha1, char typeflag, const char *basepath,
+static void write_header(const unsigned char *sha1, char typeflag, const char *basepath,
                          struct path_prefix *prefix, const char *path,
-                         unsigned int mode, unsigned long size)
+                         unsigned int mode, void *buffer, unsigned long size)
 {
 	unsigned int namelen; 
-	char *p, *header = NULL;
+	char *header = NULL;
 	unsigned int checksum = 0;
 	int i;
+	unsigned int ext_header = 0;
+
+	if (typeflag == TYPEFLAG_AUTO) {
+		if (S_ISDIR(mode))
+			typeflag = TYPEFLAG_DIR;
+		else if (S_ISLNK(mode))
+			typeflag = TYPEFLAG_LNK;
+		else
+			typeflag = TYPEFLAG_REG;
+	}
 
 	namelen = path_len(S_ISDIR(mode), basepath, prefix, path);
-	if (namelen > 500) {
-		die("tar-tree: name too log of object %s\n", sha1_to_hex(sha1));
-	} else if (namelen > 100) {
-		char *sha1_hex = sha1_to_hex(sha1);
+	if (namelen > 100)
+		ext_header |= EXT_HEADER_PATH;
+	if (typeflag == TYPEFLAG_LNK && size > 100)
+		ext_header |= EXT_HEADER_LINKPATH;
+
+	/* the extended header must be written before the normal one */
+	if (ext_header) {
 		char headerfilename[51];
-		sprintf(headerfilename, "%s.paxheader", sha1_hex);
-		/* the extended header must be written before the normal one */
-		write_extended_header(headerfilename, S_ISDIR(mode), basepath,
-				      prefix, path, namelen);
-
-		header = block + offset;
-		memset(header, 0, RECORDSIZE);
-		offset += RECORDSIZE;
-		sprintf(header, "%s.data", sha1_hex);
+		sprintf(headerfilename, "%s.paxheader", sha1_to_hex(sha1));
+		write_extended_header(headerfilename, S_ISDIR(mode),
+		                      ext_header, basepath, prefix, path,
+		                      namelen, buffer, size);
+	}
+
+	header = get_record();
+
+	if (ext_header) {
+		sprintf(header, "%s.data", sha1_to_hex(sha1));
 	} else {
-		header = block + offset;
-		memset(header, 0, RECORDSIZE);
-		offset += RECORDSIZE;
-		p = header;
+		char *p = header;
 		append_path(&p, S_ISDIR(mode), basepath, prefix, path);
 	}
 
+	if (typeflag == TYPEFLAG_LNK) {
+		if (ext_header & EXT_HEADER_LINKPATH) {
+			sprintf(&header[157], "see %s.paxheader",
+			        sha1_to_hex(sha1));
+		} else {
+			if (buffer)
+				strncpy(&header[157], buffer, size);
+		}
+	}
+
 	if (S_ISDIR(mode))
-		mode |= 0755;	/* GIT doesn't store permissions of dirs */
+		mode |= 0777;
+	else if (S_ISREG(mode))
+		mode |= (mode & 0100) ? 0777 : 0666;
+	else if (S_ISLNK(mode))
+		mode |= 0777;
 	sprintf(&header[100], "%07o", mode & 07777);
 
 	/* XXX: should we provide more meaningful info here? */
@@ -245,7 +441,9 @@ static void write_header(const char *sha1, char typeflag, const char *basepath,
 	strncpy(&header[265], "git", 31);	/* uname */
 	strncpy(&header[297], "git", 31);	/* gname */
 
-	sprintf(&header[124], "%011lo", S_ISDIR(mode) ? 0 : size);
+	if (S_ISDIR(mode) || S_ISLNK(mode))
+		size = 0;
+	sprintf(&header[124], "%011lo", size);
 	sprintf(&header[136], "%011lo", archive_time);
 
 	header[156] = typeflag;
@@ -253,8 +451,8 @@ static void write_header(const char *sha1, char typeflag, const char *basepath,
 	memcpy(&header[257], "ustar", 6);
 	memcpy(&header[263], "00", 2);
 
-	printf(&header[329], "%07o", 0);	/* devmajor */
-	printf(&header[337], "%07o", 0);	/* devminor */
+	sprintf(&header[329], "%07o", 0);	/* devmajor */
+	sprintf(&header[337], "%07o", 0);	/* devminor */
 
 	memset(&header[148], ' ', 8);
 	for (i = 0; i < RECORDSIZE; i++)
@@ -264,78 +462,59 @@ static void write_header(const char *sha1, char typeflag, const char *basepath,
 	write_if_needed();
 }
 
-static void traverse_tree(void *buffer, unsigned long size,
-			  struct path_prefix *prefix)
+static void traverse_tree(struct tree_desc *tree, struct strbuf *path)
 {
-	struct path_prefix this_prefix;
-	this_prefix.prev = prefix;
+	int pathlen = path->len;
 
-	while (size) {
-		int namelen = strlen(buffer)+1;
+	while (tree->size) {
+		const char *name;
+		const unsigned char *sha1;
+		unsigned mode;
 		void *eltbuf;
 		char elttype[20];
 		unsigned long eltsize;
-		unsigned char *sha1 = buffer + namelen;
-		char *path = strchr(buffer, ' ') + 1;
-		unsigned int mode;
 
-		if (size < namelen + 20 || sscanf(buffer, "%o", &mode) != 1)
-			die("corrupt 'tree' file");
-		buffer = sha1 + 20;
-		size -= namelen + 20;
+		sha1 = tree_entry_extract(tree, &name, &mode);
+		update_tree_entry(tree);
 
 		eltbuf = read_sha1_file(sha1, elttype, &eltsize);
 		if (!eltbuf)
 			die("cannot read %s", sha1_to_hex(sha1));
-		write_header(sha1, S_ISDIR(mode) ? '5' : '0', basedir,
-		             prefix, path, mode, eltsize);
-		if (!strcmp(elttype, "tree")) {
-			this_prefix.name = path;
-			traverse_tree(eltbuf, eltsize, &this_prefix);
-		} else if (!strcmp(elttype, "blob")) {
-			write_blocked(eltbuf, eltsize);
-		}
-		free(eltbuf);
-	}
-}
 
-/* get commit time from committer line of commit object */
-time_t commit_time(void * buffer, unsigned long size)
-{
-	time_t result = 0;
-	char *p = buffer;
+		path->len = pathlen;
+		strbuf_append_string(path, name);
+		if (S_ISDIR(mode))
+			strbuf_append_string(path, "/");
 
-	while (size > 0) {
-		char *endp = memchr(p, '\n', size);
-		if (!endp || endp == p)
-			break;
-		*endp = '\0';
-		if (endp - p > 10 && !memcmp(p, "committer ", 10)) {
-			char *nump = strrchr(p, '>');
-			if (!nump)
-				break;
-			nump++;
-			result = strtoul(nump, &endp, 10);
-			if (*endp != ' ')
-				result = 0;
-			break;
+		write_entry(sha1, path, mode, eltbuf, eltsize);
+
+		if (S_ISDIR(mode)) {
+			struct tree_desc subtree;
+			subtree.buf = eltbuf;
+			subtree.size = eltsize;
+			traverse_tree(&subtree, path);
 		}
-		size -= endp - p - 1;
-		p = endp + 1;
+		free(eltbuf);
 	}
-	return result;
 }
 
 int main(int argc, char **argv)
 {
-	unsigned char sha1[20];
-	unsigned char commit_sha1[20];
-	void *buffer;
-	unsigned long size;
+	unsigned char sha1[20], tree_sha1[20];
+	struct commit *commit;
+	struct tree_desc tree;
+	struct strbuf current_path;
+
+	current_path.buf = xmalloc(PATH_MAX);
+	current_path.alloc = PATH_MAX;
+	current_path.len = current_path.eof = 0;
+
+	setup_git_directory();
 
 	switch (argc) {
 	case 3:
-		basedir = argv[2];
+		strbuf_append_string(&current_path, argv[2]);
+		strbuf_append_string(&current_path, "/");
 		/* FALLTHROUGH */
 	case 2:
 		if (get_sha1(argv[1], sha1) < 0)
@@ -345,26 +524,23 @@ int main(int argc, char **argv)
 		usage(tar_tree_usage);
 	}
 
-	sha1_file_directory = getenv(DB_ENVIRONMENT);
-	if (!sha1_file_directory)
-		sha1_file_directory = DEFAULT_DB_ENVIRONMENT;
+	commit = lookup_commit_reference_gently(sha1, 1);
+	if (commit) {
+		write_global_extended_header(commit->object.sha1);
+		archive_time = commit->date;
+	} else
+		archive_time = time(NULL);
 
-	buffer = read_object_with_reference(sha1, "commit", &size, commit_sha1);
-	if (buffer) {
-		write_global_extended_header(commit_sha1);
-		archive_time = commit_time(buffer, size);
-		free(buffer);
-	}
-	buffer = read_object_with_reference(sha1, "tree", &size, NULL);
-	if (!buffer)
+	tree.buf = read_object_with_reference(sha1, "tree", &tree.size,
+	                                      tree_sha1);
+	if (!tree.buf)
 		die("not a reference to a tag, commit or tree object: %s",
 		    sha1_to_hex(sha1));
-	if (!archive_time)
-		archive_time = time(NULL);
-	if (basedir)
-		write_header("0", '5', NULL, NULL, basedir, 040755, 0);
-	traverse_tree(buffer, size, NULL);
-	free(buffer);
+
+	if (current_path.len > 0)
+		write_entry(tree_sha1, &current_path, 040777, NULL, 0);
+	traverse_tree(&tree, &current_path);
 	write_trailer();
+	free(current_path.buf);
 	return 0;
 }