* This handles basic git sha1 object files - packing, unpacking,
* creation etc.
*/
-#include <stdarg.h>
+#include <sys/types.h>
+#include <dirent.h>
#include "cache.h"
+#include "delta.h"
+#include "pack.h"
-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)
{
return 0;
}
+static 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 char *git_dir, *git_object_dir, *git_index_file, *git_refs_dir;
+static void setup_git_env(void)
+{
+ git_dir = gitenv(GIT_DIR_ENVIRONMENT);
+ if (!git_dir)
+ git_dir = DEFAULT_GIT_DIR_ENVIRONMENT;
+ git_object_dir = gitenv(DB_ENVIRONMENT);
+ if (!git_object_dir) {
+ git_object_dir = xmalloc(strlen(git_dir) + 9);
+ sprintf(git_object_dir, "%s/objects", git_dir);
+ }
+ git_refs_dir = xmalloc(strlen(git_dir) + 6);
+ sprintf(git_refs_dir, "%s/refs", git_dir);
+ git_index_file = gitenv(INDEX_ENVIRONMENT);
+ if (!git_index_file) {
+ git_index_file = xmalloc(strlen(git_dir) + 7);
+ sprintf(git_index_file, "%s/index", git_dir);
+ }
+}
+
+char *get_object_directory(void)
+{
+ if (!git_object_dir)
+ setup_git_env();
+ return git_object_dir;
+}
+
+char *get_refs_directory(void)
+{
+ if (!git_refs_dir)
+ setup_git_env();
+ return git_refs_dir;
+}
+
+char *get_index_file(void)
+{
+ if (!git_index_file)
+ setup_git_env();
+ return git_index_file;
+}
+
+char *git_path(const char *fmt, ...)
+{
+ static char pathname[PATH_MAX], *ret;
+ va_list args;
+ int len;
+
+ if (!git_dir)
+ setup_git_env();
+ len = strlen(git_dir);
+ if (len > PATH_MAX-100)
+ return "pad-path";
+ memcpy(pathname, git_dir, len);
+ if (len && git_dir[len-1] != '/')
+ pathname[len++] = '/';
+ va_start(args, fmt);
+ vsnprintf(pathname + len, sizeof(pathname) - len, fmt, args);
+ va_end(args);
+ ret = pathname;
+
+ /* Clean it up */
+ if (!memcmp(pathname, "./", 2)) {
+ ret += 2;
+ while (*ret == '/')
+ ret++;
+ }
+ return ret;
+}
+
+int safe_create_leading_directories(char *path)
+{
+ char *pos = path;
+
+ while (pos) {
+ pos = strchr(pos, '/');
+ if (!pos)
+ break;
+ *pos = 0;
+ if (mkdir(path, 0777) < 0)
+ if (errno != EEXIST) {
+ *pos = '/';
+ return -1;
+ }
+ *pos++ = '/';
+ }
+ return 0;
+}
+
+int get_sha1(const char *str, unsigned char *sha1)
+{
+ static const char *prefix[] = {
+ "",
+ "refs",
+ "refs/tags",
+ "refs/heads",
+ "refs/snap",
+ NULL
+ };
+ const char **p;
+
+ if (!get_sha1_hex(str, sha1))
+ return 0;
+
+ for (p = prefix; *p; p++) {
+ char * pathname = git_path("%s/%s", *p, str);
+ if (!get_sha1_file(pathname, sha1))
+ return 0;
+ }
+
+ return -1;
+}
+
char * sha1_to_hex(const unsigned char *sha1)
{
static char buffer[50];
return buffer;
}
+static void fill_sha1_path(char *pathbuf, const unsigned char *sha1)
+{
+ int i;
+ for (i = 0; i < 20; i++) {
+ static char hex[] = "0123456789abcdef";
+ unsigned int val = sha1[i];
+ char *pos = pathbuf + i*2 + (i > 0);
+ *pos++ = hex[val >> 4];
+ *pos = hex[val & 0xf];
+ }
+}
+
/*
* NOTE! This returns a statically allocated buffer, so you have to be
* careful about using it. Do a "strdup()" if you need to save the
* filename.
+ *
+ * Also note that this returns the location for creating. Reading
+ * SHA1 file can happen from any alternate directory listed in the
+ * DB_ENVIRONMENT environment variable if it is not found in
+ * the primary object database.
*/
char *sha1_file_name(const unsigned char *sha1)
{
- int i;
static char *name, *base;
if (!base) {
- char *sha1_file_directory = getenv(DB_ENVIRONMENT) ? : DEFAULT_DB_ENVIRONMENT;
+ const char *sha1_file_directory = get_object_directory();
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] = '/';
base[len+3] = '/';
name = base + len + 1;
}
- for (i = 0; i < 20; i++) {
- static char hex[] = "0123456789abcdef";
- unsigned int val = sha1[i];
- char *pos = name + i*2 + (i > 0);
- *pos++ = hex[val >> 4];
- *pos = hex[val & 0xf];
- }
+ fill_sha1_path(name, sha1);
return base;
}
-int check_sha1_signature(unsigned char *sha1, void *map, unsigned long size)
+struct alternate_object_database *alt_odb;
+
+/*
+ * Prepare alternate object database registry.
+ * alt_odb points at an array of struct alternate_object_database.
+ * This array is terminated with an element that has both its base
+ * and name set to NULL. alt_odb[n] comes from n'th non-empty
+ * element from colon separated ALTERNATE_DB_ENVIRONMENT environment
+ * variable, and its base points at a statically allocated buffer
+ * that contains "/the/directory/corresponding/to/.git/objects/...",
+ * while its name points just after the slash at the end of
+ * ".git/objects/" in the example above, and has enough space to hold
+ * 40-byte hex SHA1, an extra slash for the first level indirection,
+ * and the terminating NUL.
+ * This function allocates the alt_odb array and all the strings
+ * pointed by base fields of the array elements with one xmalloc();
+ * the string pool immediately follows the array.
+ */
+void prepare_alt_odb(void)
+{
+ int pass, totlen, i;
+ const char *cp, *last;
+ char *op = NULL;
+ const char *alt = gitenv(ALTERNATE_DB_ENVIRONMENT) ? : "";
+
+ if (alt_odb)
+ return;
+ /* The first pass counts how large an area to allocate to
+ * hold the entire alt_odb structure, including array of
+ * structs and path buffers for them. The second pass fills
+ * the structure and prepares the path buffers for use by
+ * fill_sha1_path().
+ */
+ for (totlen = pass = 0; pass < 2; pass++) {
+ last = alt;
+ i = 0;
+ do {
+ cp = strchr(last, ':') ? : last + strlen(last);
+ if (last != cp) {
+ /* 43 = 40-byte + 2 '/' + terminating NUL */
+ int pfxlen = cp - last;
+ int entlen = pfxlen + 43;
+ if (pass == 0)
+ totlen += entlen;
+ else {
+ alt_odb[i].base = op;
+ alt_odb[i].name = op + pfxlen + 1;
+ memcpy(op, last, pfxlen);
+ op[pfxlen] = op[pfxlen + 3] = '/';
+ op[entlen-1] = 0;
+ op += entlen;
+ }
+ i++;
+ }
+ while (*cp && *cp == ':')
+ cp++;
+ last = cp;
+ } while (*cp);
+ if (pass)
+ break;
+ alt_odb = xmalloc(sizeof(*alt_odb) * (i + 1) + totlen);
+ alt_odb[i].base = alt_odb[i].name = NULL;
+ op = (char*)(&alt_odb[i+1]);
+ }
+}
+
+static char *find_sha1_file(const unsigned char *sha1, struct stat *st)
+{
+ int i;
+ char *name = sha1_file_name(sha1);
+
+ if (!stat(name, st))
+ return name;
+ prepare_alt_odb();
+ for (i = 0; (name = alt_odb[i].name) != NULL; i++) {
+ fill_sha1_path(name, sha1);
+ if (!stat(alt_odb[i].base, st))
+ return alt_odb[i].base;
+ }
+ return NULL;
+}
+
+#define PACK_MAX_SZ (1<<26)
+static int pack_used_ctr;
+static unsigned long pack_mapped;
+struct packed_git *packed_git;
+
+static int check_packed_git_idx(const char *path, unsigned long *idx_size_,
+ void **idx_map_)
+{
+ void *idx_map;
+ unsigned int *index;
+ unsigned long idx_size;
+ int nr, i;
+ int fd = open(path, O_RDONLY);
+ struct stat st;
+ if (fd < 0)
+ return -1;
+ if (fstat(fd, &st)) {
+ close(fd);
+ return -1;
+ }
+ idx_size = st.st_size;
+ idx_map = mmap(NULL, idx_size, PROT_READ, MAP_PRIVATE, fd, 0);
+ close(fd);
+ if (idx_map == MAP_FAILED)
+ return -1;
+
+ index = idx_map;
+ *idx_map_ = idx_map;
+ *idx_size_ = idx_size;
+
+ /* check index map */
+ if (idx_size < 4*256 + 20 + 20)
+ return error("index file too small");
+ nr = 0;
+ for (i = 0; i < 256; i++) {
+ unsigned int n = ntohl(index[i]);
+ if (n < nr)
+ return error("non-monotonic index");
+ nr = n;
+ }
+
+ /*
+ * Total size:
+ * - 256 index entries 4 bytes each
+ * - 24-byte entries * nr (20-byte sha1 + 4-byte offset)
+ * - 20-byte SHA1 of the packfile
+ * - 20-byte SHA1 file checksum
+ */
+ if (idx_size != 4*256 + nr * 24 + 20 + 20)
+ return error("wrong index file size");
+
+ return 0;
+}
+
+static int unuse_one_packed_git(void)
+{
+ struct packed_git *p, *lru = NULL;
+
+ for (p = packed_git; p; p = p->next) {
+ if (p->pack_use_cnt || !p->pack_base)
+ continue;
+ if (!lru || p->pack_last_used < lru->pack_last_used)
+ lru = p;
+ }
+ if (!lru)
+ return 0;
+ munmap(lru->pack_base, lru->pack_size);
+ lru->pack_base = NULL;
+ return 1;
+}
+
+void unuse_packed_git(struct packed_git *p)
+{
+ p->pack_use_cnt--;
+}
+
+int use_packed_git(struct packed_git *p)
+{
+ if (!p->pack_base) {
+ int fd;
+ struct stat st;
+ void *map;
+
+ pack_mapped += p->pack_size;
+ while (PACK_MAX_SZ < pack_mapped && unuse_one_packed_git())
+ ; /* nothing */
+ fd = open(p->pack_name, O_RDONLY);
+ if (fd < 0)
+ die("packfile %s cannot be opened", p->pack_name);
+ if (fstat(fd, &st)) {
+ close(fd);
+ die("packfile %s cannot be opened", p->pack_name);
+ }
+ if (st.st_size != p->pack_size)
+ die("packfile %s size mismatch.", p->pack_name);
+ map = mmap(NULL, p->pack_size, PROT_READ, MAP_PRIVATE, fd, 0);
+ close(fd);
+ if (map == MAP_FAILED)
+ die("packfile %s cannot be mapped.", p->pack_name);
+ p->pack_base = map;
+
+ /* Check if the pack file matches with the index file.
+ * this is cheap.
+ */
+ if (memcmp((char*)(p->index_base) + p->index_size - 40,
+ p->pack_base + p->pack_size - 20, 20))
+ die("packfile %s does not match index.", p->pack_name);
+ }
+ p->pack_last_used = pack_used_ctr++;
+ p->pack_use_cnt++;
+ return 0;
+}
+
+struct packed_git *add_packed_git(char *path, int path_len)
{
+ struct stat st;
+ struct packed_git *p;
+ unsigned long idx_size;
+ void *idx_map;
+
+ if (check_packed_git_idx(path, &idx_size, &idx_map))
+ return NULL;
+
+ /* do we have a corresponding .pack file? */
+ strcpy(path + path_len - 4, ".pack");
+ if (stat(path, &st) || !S_ISREG(st.st_mode)) {
+ munmap(idx_map, idx_size);
+ return NULL;
+ }
+ /* ok, it looks sane as far as we can check without
+ * actually mapping the pack file.
+ */
+ p = xmalloc(sizeof(*p) + path_len + 2);
+ strcpy(p->pack_name, path);
+ p->index_size = idx_size;
+ p->pack_size = st.st_size;
+ p->index_base = idx_map;
+ p->next = NULL;
+ p->pack_base = NULL;
+ p->pack_last_used = 0;
+ p->pack_use_cnt = 0;
+ return p;
+}
+
+static void prepare_packed_git_one(char *objdir)
+{
+ char path[PATH_MAX];
+ int len;
+ DIR *dir;
+ struct dirent *de;
+
+ sprintf(path, "%s/pack", objdir);
+ len = strlen(path);
+ dir = opendir(path);
+ if (!dir)
+ return;
+ path[len++] = '/';
+ while ((de = readdir(dir)) != NULL) {
+ int namelen = strlen(de->d_name);
+ struct packed_git *p;
+
+ if (strcmp(de->d_name + namelen - 4, ".idx"))
+ continue;
+
+ /* we have .idx. Is it a file we can map? */
+ strcpy(path + len, de->d_name);
+ p = add_packed_git(path, len + namelen);
+ if (!p)
+ continue;
+ p->next = packed_git;
+ packed_git = p;
+ }
+ closedir(dir);
+}
+
+void prepare_packed_git(void)
+{
+ int i;
+ static int run_once = 0;
+
+ if (run_once++)
+ return;
+
+ prepare_packed_git_one(get_object_directory());
+ prepare_alt_odb();
+ for (i = 0; alt_odb[i].base != NULL; i++) {
+ alt_odb[i].name[0] = 0;
+ prepare_packed_git_one(alt_odb[i].base);
+ }
+}
+
+int check_sha1_signature(const unsigned char *sha1, void *map, unsigned long size, const char *type)
+{
+ char header[100];
unsigned char real_sha1[20];
SHA_CTX c;
SHA1_Init(&c);
+ SHA1_Update(&c, header, 1+sprintf(header, "%s %lu", type, size));
SHA1_Update(&c, map, size);
SHA1_Final(real_sha1, &c);
return memcmp(sha1, real_sha1, 20) ? -1 : 0;
}
-void *map_sha1_file(const unsigned char *sha1, unsigned long *size)
+static void *map_sha1_file_internal(const unsigned char *sha1,
+ unsigned long *size,
+ int say_error)
{
- char *filename = sha1_file_name(sha1);
- int fd = open(filename, O_RDONLY);
struct stat st;
void *map;
+ int fd;
+ char *filename = find_sha1_file(sha1, &st);
- if (fd < 0) {
- perror(filename);
+ if (!filename) {
+ if (say_error)
+ error("cannot map sha1 file %s", sha1_to_hex(sha1));
return NULL;
}
- if (fstat(fd, &st) < 0) {
- close(fd);
- return NULL;
+
+ fd = open(filename, O_RDONLY | sha1_file_open_flag);
+ if (fd < 0) {
+ /* 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:
+ if (say_error)
+ perror(filename);
+ return NULL;
+ }
+
+ /* If it failed once, it will probably fail again.
+ * Stop using O_NOATIME
+ */
+ sha1_file_open_flag = 0;
}
map = mmap(NULL, st.st_size, PROT_READ, MAP_PRIVATE, fd, 0);
close(fd);
return map;
}
+void *map_sha1_file(const unsigned char *sha1, unsigned long *size)
+{
+ return map_sha1_file_internal(sha1, size, 1);
+}
+
+int unpack_sha1_header(z_stream *stream, void *map, unsigned long mapsize, void *buffer, unsigned long size)
+{
+ /* Get the data stream */
+ memset(stream, 0, sizeof(*stream));
+ stream->next_in = map;
+ stream->avail_in = mapsize;
+ stream->next_out = buffer;
+ stream->avail_out = size;
+
+ inflateInit(stream);
+ return inflate(stream, 0);
+}
+
+static void *unpack_sha1_rest(z_stream *stream, void *buffer, unsigned long size)
+{
+ int bytes = strlen(buffer) + 1;
+ unsigned char *buf = xmalloc(1+size);
+
+ memcpy(buf, buffer + bytes, stream->total_out - bytes);
+ bytes = stream->total_out - bytes;
+ if (bytes < size) {
+ stream->next_out = buf + bytes;
+ stream->avail_out = size - bytes;
+ while (inflate(stream, Z_FINISH) == Z_OK)
+ /* nothing */;
+ }
+ buf[size] = 0;
+ inflateEnd(stream);
+ return buf;
+}
+
+/*
+ * We used to just use "sscanf()", but that's actually way
+ * too permissive for what we want to check. So do an anal
+ * object header parse by hand.
+ */
+int parse_sha1_header(char *hdr, char *type, unsigned long *sizep)
+{
+ int i;
+ unsigned long size;
+
+ /*
+ * The type can be at most ten bytes (including the
+ * terminating '\0' that we add), and is followed by
+ * a space.
+ */
+ i = 10;
+ for (;;) {
+ char c = *hdr++;
+ if (c == ' ')
+ break;
+ if (!--i)
+ return -1;
+ *type++ = c;
+ }
+ *type = 0;
+
+ /*
+ * The length must follow immediately, and be in canonical
+ * decimal format (ie "010" is not valid).
+ */
+ size = *hdr++ - '0';
+ if (size > 9)
+ return -1;
+ if (size) {
+ for (;;) {
+ unsigned long c = *hdr - '0';
+ if (c > 9)
+ break;
+ hdr++;
+ size = size * 10 + c;
+ }
+ }
+ *sizep = size;
+
+ /*
+ * The length must be followed by a zero byte
+ */
+ return *hdr ? -1 : 0;
+}
+
void * unpack_sha1_file(void *map, unsigned long mapsize, char *type, unsigned long *size)
{
- int ret, bytes;
+ int ret;
z_stream stream;
- char buffer[8192];
- char *buf;
+ char hdr[8192];
+
+ ret = unpack_sha1_header(&stream, map, mapsize, hdr, sizeof(hdr));
+ if (ret < Z_OK || parse_sha1_header(hdr, type, size) < 0)
+ return NULL;
+
+ return unpack_sha1_rest(&stream, hdr, *size);
+}
+
+/* forward declaration for a mutually recursive function */
+static int packed_object_info(struct pack_entry *entry,
+ char *type, unsigned long *sizep);
+
+static int packed_delta_info(unsigned char *base_sha1,
+ unsigned long delta_size,
+ unsigned long left,
+ char *type,
+ unsigned long *sizep,
+ struct packed_git *p)
+{
+ struct pack_entry base_ent;
+
+ if (left < 20)
+ die("truncated pack file");
+
+ /* The base entry _must_ be in the same pack */
+ if (!find_pack_entry_one(base_sha1, &base_ent, p))
+ die("failed to find delta-pack base object %s",
+ sha1_to_hex(base_sha1));
+
+ /* We choose to only get the type of the base object and
+ * ignore potentially corrupt pack file that expects the delta
+ * based on a base with a wrong size. This saves tons of
+ * inflate() calls.
+ */
+
+ if (packed_object_info(&base_ent, type, NULL))
+ die("cannot get info for delta-pack base");
+
+ if (sizep) {
+ const unsigned char *data;
+ unsigned char delta_head[64];
+ unsigned long result_size;
+ z_stream stream;
+ int st;
+
+ memset(&stream, 0, sizeof(stream));
+
+ data = stream.next_in = base_sha1 + 20;
+ stream.avail_in = left - 20;
+ stream.next_out = delta_head;
+ stream.avail_out = sizeof(delta_head);
+
+ inflateInit(&stream);
+ st = inflate(&stream, Z_FINISH);
+ inflateEnd(&stream);
+ if ((st != Z_STREAM_END) &&
+ stream.total_out != sizeof(delta_head))
+ die("delta data unpack-initial failed");
+
+ /* Examine the initial part of the delta to figure out
+ * the result size.
+ */
+ data = delta_head;
+ get_delta_hdr_size(&data); /* ignore base size */
+
+ /* Read the result size */
+ result_size = get_delta_hdr_size(&data);
+ *sizep = result_size;
+ }
+ return 0;
+}
+
+static unsigned long unpack_object_header(struct packed_git *p, unsigned long offset,
+ enum object_type *type, unsigned long *sizep)
+{
+ unsigned shift;
+ unsigned char *pack, c;
+ unsigned long size;
+
+ if (offset >= p->pack_size)
+ die("object offset outside of pack file");
+
+ pack = p->pack_base + offset;
+ c = *pack++;
+ offset++;
+ *type = (c >> 4) & 7;
+ size = c & 15;
+ shift = 4;
+ while (c & 0x80) {
+ if (offset >= p->pack_size)
+ die("object offset outside of pack file");
+ c = *pack++;
+ offset++;
+ size += (c & 0x7f) << shift;
+ shift += 7;
+ }
+ *sizep = size;
+ return offset;
+}
+
+void packed_object_info_detail(struct pack_entry *e,
+ char *type,
+ unsigned long *size,
+ unsigned long *store_size,
+ int *delta_chain_length,
+ unsigned char *base_sha1)
+{
+ struct packed_git *p = e->p;
+ unsigned long offset, left;
+ unsigned char *pack;
+ enum object_type kind;
+
+ offset = unpack_object_header(p, e->offset, &kind, size);
+ pack = p->pack_base + offset;
+ left = p->pack_size - offset;
+ if (kind != OBJ_DELTA)
+ *delta_chain_length = 0;
+ else {
+ int chain_length = 0;
+ memcpy(base_sha1, pack, 20);
+ do {
+ struct pack_entry base_ent;
+ unsigned long junk;
+
+ find_pack_entry_one(pack, &base_ent, p);
+ offset = unpack_object_header(p, base_ent.offset,
+ &kind, &junk);
+ pack = p->pack_base + offset;
+ chain_length++;
+ } while (kind == OBJ_DELTA);
+ *delta_chain_length = chain_length;
+ }
+ switch (kind) {
+ case OBJ_COMMIT:
+ strcpy(type, "commit");
+ break;
+ case OBJ_TREE:
+ strcpy(type, "tree");
+ break;
+ case OBJ_BLOB:
+ strcpy(type, "blob");
+ break;
+ case OBJ_TAG:
+ strcpy(type, "tag");
+ break;
+ default:
+ die("corrupted pack file");
+ }
+ *store_size = 0; /* notyet */
+}
+
+static int packed_object_info(struct pack_entry *entry,
+ char *type, unsigned long *sizep)
+{
+ struct packed_git *p = entry->p;
+ unsigned long offset, size, left;
+ unsigned char *pack;
+ enum object_type kind;
+ int retval;
+
+ if (use_packed_git(p))
+ die("cannot map packed file");
+
+ offset = unpack_object_header(p, entry->offset, &kind, &size);
+ pack = p->pack_base + offset;
+ left = p->pack_size - offset;
+
+ switch (kind) {
+ case OBJ_DELTA:
+ retval = packed_delta_info(pack, size, left, type, sizep, p);
+ unuse_packed_git(p);
+ return retval;
+ case OBJ_COMMIT:
+ strcpy(type, "commit");
+ break;
+ case OBJ_TREE:
+ strcpy(type, "tree");
+ break;
+ case OBJ_BLOB:
+ strcpy(type, "blob");
+ break;
+ case OBJ_TAG:
+ strcpy(type, "tag");
+ break;
+ default:
+ die("corrupted pack file");
+ }
+ if (sizep)
+ *sizep = size;
+ unuse_packed_git(p);
+ return 0;
+}
+
+/* forward declaration for a mutually recursive function */
+static void *unpack_entry(struct pack_entry *, char *, unsigned long *);
+
+static void *unpack_delta_entry(unsigned char *base_sha1,
+ unsigned long delta_size,
+ unsigned long left,
+ char *type,
+ unsigned long *sizep,
+ struct packed_git *p)
+{
+ struct pack_entry base_ent;
+ void *data, *delta_data, *result, *base;
+ unsigned long data_size, result_size, base_size;
+ z_stream stream;
+ int st;
+
+ if (left < 20)
+ die("truncated pack file");
+ data = base_sha1 + 20;
+ data_size = left - 20;
+ delta_data = xmalloc(delta_size);
- /* Get the data stream */
memset(&stream, 0, sizeof(stream));
- stream.next_in = map;
- stream.avail_in = mapsize;
+
+ stream.next_in = data;
+ stream.avail_in = data_size;
+ stream.next_out = delta_data;
+ stream.avail_out = delta_size;
+
+ inflateInit(&stream);
+ st = inflate(&stream, Z_FINISH);
+ inflateEnd(&stream);
+ if ((st != Z_STREAM_END) || stream.total_out != delta_size)
+ die("delta data unpack failed");
+
+ /* The base entry _must_ be in the same pack */
+ if (!find_pack_entry_one(base_sha1, &base_ent, p))
+ die("failed to find delta-pack base object %s",
+ sha1_to_hex(base_sha1));
+ base = unpack_entry_gently(&base_ent, type, &base_size);
+ if (!base)
+ die("failed to read delta-pack base object %s",
+ sha1_to_hex(base_sha1));
+ result = patch_delta(base, base_size,
+ delta_data, delta_size,
+ &result_size);
+ if (!result)
+ die("failed to apply delta");
+ free(delta_data);
+ free(base);
+ *sizep = result_size;
+ return result;
+}
+
+static void *unpack_non_delta_entry(unsigned char *data,
+ unsigned long size,
+ unsigned long left)
+{
+ int st;
+ z_stream stream;
+ unsigned char *buffer;
+
+ buffer = xmalloc(size + 1);
+ buffer[size] = 0;
+ memset(&stream, 0, sizeof(stream));
+ stream.next_in = data;
+ stream.avail_in = left;
stream.next_out = buffer;
- stream.avail_out = sizeof(buffer);
+ stream.avail_out = size;
inflateInit(&stream);
- ret = inflate(&stream, 0);
- if (sscanf(buffer, "%10s %lu", type, size) != 2)
+ st = inflate(&stream, Z_FINISH);
+ inflateEnd(&stream);
+ if ((st != Z_STREAM_END) || stream.total_out != size) {
+ free(buffer);
return NULL;
+ }
- bytes = strlen(buffer) + 1;
- buf = malloc(*size);
- if (!buf)
+ return buffer;
+}
+
+static void *unpack_entry(struct pack_entry *entry,
+ char *type, unsigned long *sizep)
+{
+ struct packed_git *p = entry->p;
+ void *retval;
+
+ if (use_packed_git(p))
+ die("cannot map packed file");
+ retval = unpack_entry_gently(entry, type, sizep);
+ unuse_packed_git(p);
+ if (!retval)
+ die("corrupted pack file");
+ return retval;
+}
+
+/* The caller is responsible for use_packed_git()/unuse_packed_git() pair */
+void *unpack_entry_gently(struct pack_entry *entry,
+ char *type, unsigned long *sizep)
+{
+ struct packed_git *p = entry->p;
+ unsigned long offset, size, left;
+ unsigned char *pack;
+ enum object_type kind;
+ void *retval;
+
+ offset = unpack_object_header(p, entry->offset, &kind, &size);
+ pack = p->pack_base + offset;
+ left = p->pack_size - offset;
+ switch (kind) {
+ case OBJ_DELTA:
+ retval = unpack_delta_entry(pack, size, left, type, sizep, p);
+ return retval;
+ case OBJ_COMMIT:
+ strcpy(type, "commit");
+ break;
+ case OBJ_TREE:
+ strcpy(type, "tree");
+ break;
+ case OBJ_BLOB:
+ strcpy(type, "blob");
+ break;
+ case OBJ_TAG:
+ strcpy(type, "tag");
+ break;
+ default:
return NULL;
+ }
+ *sizep = size;
+ retval = unpack_non_delta_entry(pack, size, left);
+ return retval;
+}
- memcpy(buf, buffer + bytes, stream.total_out - bytes);
- bytes = stream.total_out - bytes;
- if (bytes < *size && ret == Z_OK) {
- stream.next_out = buf + bytes;
- stream.avail_out = *size - bytes;
- while (inflate(&stream, Z_FINISH) == Z_OK)
- /* nothing */;
+int num_packed_objects(const struct packed_git *p)
+{
+ /* See check_packed_git_idx() */
+ return (p->index_size - 20 - 20 - 4*256) / 24;
+}
+
+int nth_packed_object_sha1(const struct packed_git *p, int n,
+ unsigned char* sha1)
+{
+ void *index = p->index_base + 256;
+ if (n < 0 || num_packed_objects(p) <= n)
+ return -1;
+ memcpy(sha1, (index + 24 * n + 4), 20);
+ return 0;
+}
+
+int find_pack_entry_one(const unsigned char *sha1,
+ struct pack_entry *e, struct packed_git *p)
+{
+ unsigned int *level1_ofs = p->index_base;
+ int hi = ntohl(level1_ofs[*sha1]);
+ int lo = ((*sha1 == 0x0) ? 0 : ntohl(level1_ofs[*sha1 - 1]));
+ void *index = p->index_base + 256;
+
+ do {
+ int mi = (lo + hi) / 2;
+ int cmp = memcmp(index + 24 * mi + 4, sha1, 20);
+ if (!cmp) {
+ e->offset = ntohl(*((int*)(index + 24 * mi)));
+ memcpy(e->sha1, sha1, 20);
+ e->p = p;
+ return 1;
+ }
+ if (cmp > 0)
+ hi = mi;
+ else
+ lo = mi+1;
+ } while (lo < hi);
+ return 0;
+}
+
+static int find_pack_entry(const unsigned char *sha1, struct pack_entry *e)
+{
+ struct packed_git *p;
+ prepare_packed_git();
+
+ for (p = packed_git; p; p = p->next) {
+ if (find_pack_entry_one(sha1, e, p))
+ return 1;
+ }
+ return 0;
+}
+
+int sha1_object_info(const unsigned char *sha1, char *type, unsigned long *sizep)
+{
+ int status;
+ unsigned long mapsize, size;
+ void *map;
+ z_stream stream;
+ char hdr[128];
+
+ map = map_sha1_file_internal(sha1, &mapsize, 0);
+ if (!map) {
+ struct pack_entry e;
+
+ if (!find_pack_entry(sha1, &e))
+ return error("unable to find %s", sha1_to_hex(sha1));
+ return packed_object_info(&e, type, sizep);
+ }
+ if (unpack_sha1_header(&stream, map, mapsize, hdr, sizeof(hdr)) < 0)
+ status = error("unable to unpack %s header",
+ sha1_to_hex(sha1));
+ if (parse_sha1_header(hdr, type, &size) < 0)
+ status = error("unable to parse %s header", sha1_to_hex(sha1));
+ else {
+ status = 0;
+ if (sizep)
+ *sizep = size;
}
inflateEnd(&stream);
- return buf;
+ munmap(map, mapsize);
+ return status;
+}
+
+static void *read_packed_sha1(const unsigned char *sha1, char *type, unsigned long *size)
+{
+ struct pack_entry e;
+
+ if (!find_pack_entry(sha1, &e)) {
+ error("cannot read sha1_file for %s", sha1_to_hex(sha1));
+ return NULL;
+ }
+ return unpack_entry(&e, type, size);
}
void * read_sha1_file(const unsigned char *sha1, char *type, unsigned long *size)
unsigned long mapsize;
void *map, *buf;
- map = map_sha1_file(sha1, &mapsize);
+ map = map_sha1_file_internal(sha1, &mapsize, 0);
if (map) {
buf = unpack_sha1_file(map, mapsize, type, size);
munmap(map, mapsize);
return buf;
}
- return NULL;
+ return read_packed_sha1(sha1, type, size);
}
-int write_sha1_file(char *buf, unsigned len, unsigned char *returnsha1)
+void *read_object_with_reference(const unsigned char *sha1,
+ const 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. */
+ }
+}
+
+static char *write_sha1_file_prepare(void *buf,
+ unsigned long len,
+ const char *type,
+ unsigned char *sha1,
+ unsigned char *hdr,
+ int *hdrlen)
+{
+ SHA_CTX c;
+
+ /* Generate the header */
+ *hdrlen = sprintf((char *)hdr, "%s %lu", type, len)+1;
+
+ /* Sha1.. */
+ SHA1_Init(&c);
+ SHA1_Update(&c, hdr, *hdrlen);
+ SHA1_Update(&c, buf, len);
+ SHA1_Final(sha1, &c);
+
+ return sha1_file_name(sha1);
+}
+
+int write_sha1_file(void *buf, unsigned long len, const char *type, unsigned char *returnsha1)
{
int size;
- char *compressed;
+ unsigned char *compressed;
z_stream stream;
unsigned char sha1[20];
- SHA_CTX c;
+ char *filename;
+ static char tmpfile[PATH_MAX];
+ unsigned char hdr[50];
+ int fd, hdrlen, ret;
+
+ /* Normally if we have it in the pack then we do not bother writing
+ * it out into .git/objects/??/?{38} file.
+ */
+ filename = write_sha1_file_prepare(buf, len, type, sha1, hdr, &hdrlen);
+ if (returnsha1)
+ memcpy(returnsha1, sha1, 20);
+ if (has_sha1_file(sha1))
+ return 0;
+ fd = open(filename, O_RDONLY);
+ if (fd >= 0) {
+ /*
+ * FIXME!!! We might do collision checking here, but we'd
+ * need to uncompress the old file and check it. Later.
+ */
+ close(fd);
+ return 0;
+ }
+
+ if (errno != ENOENT) {
+ fprintf(stderr, "sha1 file %s: %s", filename, strerror(errno));
+ return -1;
+ }
+
+ snprintf(tmpfile, sizeof(tmpfile), "%s/obj_XXXXXX", get_object_directory());
+
+ fd = mkstemp(tmpfile);
+ if (fd < 0) {
+ fprintf(stderr, "unable to create temporary sha1 filename %s: %s", tmpfile, strerror(errno));
+ return -1;
+ }
/* 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);
size = stream.total_out;
- /* Sha1.. */
- SHA1_Init(&c);
- SHA1_Update(&c, compressed, size);
- SHA1_Final(sha1, &c);
+ if (write(fd, compressed, size) != size)
+ die("unable to write file");
+ fchmod(fd, 0444);
+ close(fd);
+ free(compressed);
+
+ ret = link(tmpfile, filename);
+ if (ret < 0) {
+ ret = errno;
+
+ /*
+ * Coda hack - coda doesn't like cross-directory links,
+ * so we fall back to a rename, which will mean that it
+ * won't be able to check collisions, but that's not a
+ * big deal.
+ *
+ * When this succeeds, we just return 0. We have nothing
+ * left to unlink.
+ */
+ if (ret == EXDEV && !rename(tmpfile, filename))
+ return 0;
+ }
+ unlink(tmpfile);
+ if (ret) {
+ if (ret != EEXIST) {
+ fprintf(stderr, "unable to write sha1 filename %s: %s", filename, strerror(ret));
+ return -1;
+ }
+ /* FIXME!!! Collision check here ? */
+ }
- if (write_sha1_buffer(sha1, compressed, size) < 0)
- return -1;
- if (returnsha1)
- memcpy(returnsha1, sha1, 20);
return 0;
}
-static inline int collision_check(char *filename, void *buf, unsigned int size)
+int write_sha1_from_fd(const unsigned char *sha1, int fd)
{
-#ifdef COLLISION_CHECK
- void *map;
- int fd = open(filename, O_RDONLY);
- struct stat st;
- int cmp;
+ char *filename = sha1_file_name(sha1);
- /* Unreadable object, or object went away? Strange. */
- if (fd < 0)
- return -1;
+ int local;
+ z_stream stream;
+ unsigned char real_sha1[20];
+ unsigned char buf[4096];
+ unsigned char discard[4096];
+ int ret;
+ SHA_CTX c;
- if (fstat(fd, &st) < 0 || size != st.st_size)
- return -1;
+ local = open(filename, O_WRONLY | O_CREAT | O_EXCL, 0666);
- map = mmap(NULL, size, PROT_READ, MAP_PRIVATE, fd, 0);
- close(fd);
- if (map == MAP_FAILED)
- return -1;
- cmp = memcmp(buf, map, size);
- munmap(map, size);
- if (cmp)
- return -1;
-#endif
+ 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 write_sha1_buffer(const unsigned char *sha1, void *buf, unsigned int size)
+int has_sha1_pack(const unsigned char *sha1)
{
- char *filename = sha1_file_name(sha1);
- int fd;
+ struct pack_entry e;
+ return find_pack_entry(sha1, &e);
+}
- fd = open(filename, O_WRONLY | O_CREAT | O_EXCL, 0666);
- if (fd < 0) {
- if (errno != EEXIST)
- return -1;
- if (collision_check(filename, buf, size))
- return error("SHA1 collision detected!"
- " This is bad, bad, BAD!\a\n");
- return 0;
- }
- write(fd, buf, size);
+int has_sha1_file(const unsigned char *sha1)
+{
+ struct stat st;
+ struct pack_entry e;
+
+ if (find_sha1_file(sha1, &st))
+ return 1;
+ return find_pack_entry(sha1, &e);
+}
+
+int index_fd(unsigned char *sha1, int fd, struct stat *st)
+{
+ unsigned long size = st->st_size;
+ void *buf;
+ int ret;
+
+ buf = "";
+ if (size)
+ buf = mmap(NULL, size, PROT_READ, MAP_PRIVATE, fd, 0);
close(fd);
- return 0;
+ if ((int)(long)buf == -1)
+ return -1;
+
+ ret = write_sha1_file(buf, size, "blob", sha1);
+ if (size)
+ munmap(buf, size);
+ return ret;
}