| /* |
| * Copyright (c) 2005, 2006 Rene Scharfe |
| */ |
| #include "cache.h" |
| #include "config.h" |
| #include "tar.h" |
| #include "archive.h" |
| #include "object-store.h" |
| #include "streaming.h" |
| #include "run-command.h" |
| |
| #define RECORDSIZE (512) |
| #define BLOCKSIZE (RECORDSIZE * 20) |
| |
| static char block[BLOCKSIZE]; |
| static unsigned long offset; |
| |
| static int tar_umask = 002; |
| |
| static int write_tar_filter_archive(const struct archiver *ar, |
| struct archiver_args *args); |
| |
| /* |
| * This is the max value that a ustar size header can specify, as it is fixed |
| * at 11 octal digits. POSIX specifies that we switch to extended headers at |
| * this size. |
| * |
| * Likewise for the mtime (which happens to use a buffer of the same size). |
| */ |
| #if ULONG_MAX == 0xFFFFFFFF |
| #define USTAR_MAX_SIZE ULONG_MAX |
| #else |
| #define USTAR_MAX_SIZE 077777777777UL |
| #endif |
| #if TIME_MAX == 0xFFFFFFFF |
| #define USTAR_MAX_MTIME TIME_MAX |
| #else |
| #define USTAR_MAX_MTIME 077777777777ULL |
| #endif |
| |
| /* writes out the whole block, but only if it is full */ |
| static void write_if_needed(void) |
| { |
| if (offset == BLOCKSIZE) { |
| write_or_die(1, block, BLOCKSIZE); |
| offset = 0; |
| } |
| } |
| |
| /* |
| * queues up writes, so that all our write(2) calls write exactly one |
| * full block; pads writes to RECORDSIZE |
| */ |
| static void do_write_blocked(const void *data, unsigned long size) |
| { |
| const char *buf = data; |
| |
| if (offset) { |
| unsigned long chunk = BLOCKSIZE - offset; |
| if (size < chunk) |
| chunk = size; |
| memcpy(block + offset, buf, chunk); |
| size -= chunk; |
| offset += chunk; |
| buf += chunk; |
| write_if_needed(); |
| } |
| while (size >= BLOCKSIZE) { |
| write_or_die(1, buf, BLOCKSIZE); |
| size -= BLOCKSIZE; |
| buf += BLOCKSIZE; |
| } |
| if (size) { |
| memcpy(block + offset, buf, size); |
| offset += size; |
| } |
| } |
| |
| static void finish_record(void) |
| { |
| unsigned long tail; |
| tail = offset % RECORDSIZE; |
| if (tail) { |
| memset(block + offset, 0, RECORDSIZE - tail); |
| offset += RECORDSIZE - tail; |
| } |
| write_if_needed(); |
| } |
| |
| static void write_blocked(const void *data, unsigned long size) |
| { |
| do_write_blocked(data, size); |
| finish_record(); |
| } |
| |
| /* |
| * The end of tar archives is marked by 2*512 nul bytes and after that |
| * follows the rest of the block (if any). |
| */ |
| static void write_trailer(void) |
| { |
| int tail = BLOCKSIZE - offset; |
| memset(block + offset, 0, tail); |
| write_or_die(1, block, BLOCKSIZE); |
| if (tail < 2 * RECORDSIZE) { |
| memset(block, 0, offset); |
| write_or_die(1, block, BLOCKSIZE); |
| } |
| } |
| |
| /* |
| * queues up writes, so that all our write(2) calls write exactly one |
| * full block; pads writes to RECORDSIZE |
| */ |
| static int stream_blocked(struct repository *r, const struct object_id *oid) |
| { |
| struct git_istream *st; |
| enum object_type type; |
| unsigned long sz; |
| char buf[BLOCKSIZE]; |
| ssize_t readlen; |
| |
| st = open_istream(r, oid, &type, &sz, NULL); |
| if (!st) |
| return error(_("cannot stream blob %s"), oid_to_hex(oid)); |
| for (;;) { |
| readlen = read_istream(st, buf, sizeof(buf)); |
| if (readlen <= 0) |
| break; |
| do_write_blocked(buf, readlen); |
| } |
| close_istream(st); |
| if (!readlen) |
| finish_record(); |
| return readlen; |
| } |
| |
| /* |
| * 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, size_t valuelen) |
| { |
| size_t orig_len = sb->len; |
| size_t len, tmp; |
| |
| /* "%u %s=%s\n" */ |
| len = 1 + 1 + strlen(keyword) + 1 + valuelen + 1; |
| for (tmp = 1; len / 10 >= tmp; tmp *= 10) |
| len++; |
| |
| strbuf_grow(sb, len); |
| strbuf_addf(sb, "%"PRIuMAX" %s=", (uintmax_t)len, keyword); |
| strbuf_add(sb, value, valuelen); |
| strbuf_addch(sb, '\n'); |
| |
| if (len != sb->len - orig_len) |
| BUG("pax extended header length miscalculated as %"PRIuMAX |
| ", should be %"PRIuMAX, |
| (uintmax_t)len, (uintmax_t)(sb->len - orig_len)); |
| } |
| |
| /* |
| * Like strbuf_append_ext_header, but for numeric values. |
| */ |
| static void strbuf_append_ext_header_uint(struct strbuf *sb, |
| const char *keyword, |
| uintmax_t value) |
| { |
| char buf[40]; /* big enough for 2^128 in decimal, plus NUL */ |
| int len; |
| |
| len = xsnprintf(buf, sizeof(buf), "%"PRIuMAX, value); |
| strbuf_append_ext_header(sb, keyword, buf, len); |
| } |
| |
| static unsigned int ustar_header_chksum(const struct ustar_header *header) |
| { |
| const unsigned char *p = (const unsigned char *)header; |
| unsigned int chksum = 0; |
| while (p < (const unsigned char *)header->chksum) |
| chksum += *p++; |
| chksum += sizeof(header->chksum) * ' '; |
| p += sizeof(header->chksum); |
| while (p < (const unsigned char *)header + sizeof(struct ustar_header)) |
| chksum += *p++; |
| return chksum; |
| } |
| |
| static size_t get_path_prefix(const char *path, size_t pathlen, size_t maxlen) |
| { |
| size_t i = pathlen; |
| if (i > 1 && path[i - 1] == '/') |
| i--; |
| if (i > maxlen) |
| i = maxlen; |
| do { |
| i--; |
| } while (i > 0 && path[i] != '/'); |
| return i; |
| } |
| |
| static void prepare_header(struct archiver_args *args, |
| struct ustar_header *header, |
| unsigned int mode, unsigned long size) |
| { |
| xsnprintf(header->mode, sizeof(header->mode), "%07o", mode & 07777); |
| xsnprintf(header->size, sizeof(header->size), "%011"PRIoMAX , S_ISREG(mode) ? (uintmax_t)size : (uintmax_t)0); |
| xsnprintf(header->mtime, sizeof(header->mtime), "%011lo", (unsigned long) args->time); |
| |
| xsnprintf(header->uid, sizeof(header->uid), "%07o", 0); |
| xsnprintf(header->gid, sizeof(header->gid), "%07o", 0); |
| strlcpy(header->uname, "root", sizeof(header->uname)); |
| strlcpy(header->gname, "root", sizeof(header->gname)); |
| xsnprintf(header->devmajor, sizeof(header->devmajor), "%07o", 0); |
| xsnprintf(header->devminor, sizeof(header->devminor), "%07o", 0); |
| |
| memcpy(header->magic, "ustar", 6); |
| memcpy(header->version, "00", 2); |
| |
| xsnprintf(header->chksum, sizeof(header->chksum), "%07o", ustar_header_chksum(header)); |
| } |
| |
| static void write_extended_header(struct archiver_args *args, |
| const struct object_id *oid, |
| const void *buffer, unsigned long size) |
| { |
| struct ustar_header header; |
| unsigned int mode; |
| memset(&header, 0, sizeof(header)); |
| *header.typeflag = TYPEFLAG_EXT_HEADER; |
| mode = 0100666; |
| xsnprintf(header.name, sizeof(header.name), "%s.paxheader", oid_to_hex(oid)); |
| prepare_header(args, &header, mode, size); |
| write_blocked(&header, sizeof(header)); |
| write_blocked(buffer, size); |
| } |
| |
| static int write_tar_entry(struct archiver_args *args, |
| const struct object_id *oid, |
| const char *path, size_t pathlen, |
| unsigned int mode, |
| void *buffer, unsigned long size) |
| { |
| struct ustar_header header; |
| struct strbuf ext_header = STRBUF_INIT; |
| unsigned long size_in_header; |
| int err = 0; |
| |
| memset(&header, 0, sizeof(header)); |
| |
| if (S_ISDIR(mode) || S_ISGITLINK(mode)) { |
| *header.typeflag = TYPEFLAG_DIR; |
| mode = (mode | 0777) & ~tar_umask; |
| } else if (S_ISLNK(mode)) { |
| *header.typeflag = TYPEFLAG_LNK; |
| mode |= 0777; |
| } else if (S_ISREG(mode)) { |
| *header.typeflag = TYPEFLAG_REG; |
| mode = (mode | ((mode & 0100) ? 0777 : 0666)) & ~tar_umask; |
| } else { |
| return error(_("unsupported file mode: 0%o (SHA1: %s)"), |
| mode, oid_to_hex(oid)); |
| } |
| if (pathlen > sizeof(header.name)) { |
| size_t plen = get_path_prefix(path, pathlen, |
| sizeof(header.prefix)); |
| size_t rest = pathlen - plen - 1; |
| if (plen > 0 && rest <= sizeof(header.name)) { |
| memcpy(header.prefix, path, plen); |
| memcpy(header.name, path + plen + 1, rest); |
| } else { |
| xsnprintf(header.name, sizeof(header.name), "%s.data", |
| oid_to_hex(oid)); |
| strbuf_append_ext_header(&ext_header, "path", |
| path, pathlen); |
| } |
| } else |
| memcpy(header.name, path, pathlen); |
| |
| if (S_ISLNK(mode)) { |
| if (size > sizeof(header.linkname)) { |
| xsnprintf(header.linkname, sizeof(header.linkname), |
| "see %s.paxheader", oid_to_hex(oid)); |
| strbuf_append_ext_header(&ext_header, "linkpath", |
| buffer, size); |
| } else |
| memcpy(header.linkname, buffer, size); |
| } |
| |
| size_in_header = size; |
| if (S_ISREG(mode) && size > USTAR_MAX_SIZE) { |
| size_in_header = 0; |
| strbuf_append_ext_header_uint(&ext_header, "size", size); |
| } |
| |
| prepare_header(args, &header, mode, size_in_header); |
| |
| if (ext_header.len > 0) { |
| write_extended_header(args, oid, ext_header.buf, |
| ext_header.len); |
| } |
| strbuf_release(&ext_header); |
| write_blocked(&header, sizeof(header)); |
| if (S_ISREG(mode) && size > 0) { |
| if (buffer) |
| write_blocked(buffer, size); |
| else |
| err = stream_blocked(args->repo, oid); |
| } |
| return err; |
| } |
| |
| static void write_global_extended_header(struct archiver_args *args) |
| { |
| const struct object_id *oid = args->commit_oid; |
| struct strbuf ext_header = STRBUF_INIT; |
| struct ustar_header header; |
| unsigned int mode; |
| |
| if (oid) |
| strbuf_append_ext_header(&ext_header, "comment", |
| oid_to_hex(oid), |
| the_hash_algo->hexsz); |
| if (args->time > USTAR_MAX_MTIME) { |
| strbuf_append_ext_header_uint(&ext_header, "mtime", |
| args->time); |
| args->time = USTAR_MAX_MTIME; |
| } |
| |
| if (!ext_header.len) |
| return; |
| |
| memset(&header, 0, sizeof(header)); |
| *header.typeflag = TYPEFLAG_GLOBAL_HEADER; |
| mode = 0100666; |
| xsnprintf(header.name, sizeof(header.name), "pax_global_header"); |
| prepare_header(args, &header, mode, ext_header.len); |
| write_blocked(&header, sizeof(header)); |
| write_blocked(ext_header.buf, ext_header.len); |
| strbuf_release(&ext_header); |
| } |
| |
| static struct archiver **tar_filters; |
| static int nr_tar_filters; |
| static int alloc_tar_filters; |
| |
| static struct archiver *find_tar_filter(const char *name, size_t len) |
| { |
| int i; |
| for (i = 0; i < nr_tar_filters; i++) { |
| struct archiver *ar = tar_filters[i]; |
| if (!strncmp(ar->name, name, len) && !ar->name[len]) |
| return ar; |
| } |
| return NULL; |
| } |
| |
| static int tar_filter_config(const char *var, const char *value, void *data) |
| { |
| struct archiver *ar; |
| const char *name; |
| const char *type; |
| size_t namelen; |
| |
| if (parse_config_key(var, "tar", &name, &namelen, &type) < 0 || !name) |
| return 0; |
| |
| ar = find_tar_filter(name, namelen); |
| if (!ar) { |
| ar = xcalloc(1, sizeof(*ar)); |
| ar->name = xmemdupz(name, namelen); |
| ar->write_archive = write_tar_filter_archive; |
| ar->flags = ARCHIVER_WANT_COMPRESSION_LEVELS | |
| ARCHIVER_HIGH_COMPRESSION_LEVELS; |
| ALLOC_GROW(tar_filters, nr_tar_filters + 1, alloc_tar_filters); |
| tar_filters[nr_tar_filters++] = ar; |
| } |
| |
| if (!strcmp(type, "command")) { |
| if (!value) |
| return config_error_nonbool(var); |
| free(ar->data); |
| ar->data = xstrdup(value); |
| return 0; |
| } |
| if (!strcmp(type, "remote")) { |
| if (git_config_bool(var, value)) |
| ar->flags |= ARCHIVER_REMOTE; |
| else |
| ar->flags &= ~ARCHIVER_REMOTE; |
| return 0; |
| } |
| |
| return 0; |
| } |
| |
| static int git_tar_config(const char *var, const char *value, void *cb) |
| { |
| if (!strcmp(var, "tar.umask")) { |
| if (value && !strcmp(value, "user")) { |
| tar_umask = umask(0); |
| umask(tar_umask); |
| } else { |
| tar_umask = git_config_int(var, value); |
| } |
| return 0; |
| } |
| |
| return tar_filter_config(var, value, cb); |
| } |
| |
| static int write_tar_archive(const struct archiver *ar, |
| struct archiver_args *args) |
| { |
| int err = 0; |
| |
| write_global_extended_header(args); |
| err = write_archive_entries(args, write_tar_entry); |
| if (!err) |
| write_trailer(); |
| return err; |
| } |
| |
| static int write_tar_filter_archive(const struct archiver *ar, |
| struct archiver_args *args) |
| { |
| struct strbuf cmd = STRBUF_INIT; |
| struct child_process filter = CHILD_PROCESS_INIT; |
| const char *argv[2]; |
| int r; |
| |
| if (!ar->data) |
| BUG("tar-filter archiver called with no filter defined"); |
| |
| strbuf_addstr(&cmd, ar->data); |
| if (args->compression_level >= 0) |
| strbuf_addf(&cmd, " -%d", args->compression_level); |
| |
| argv[0] = cmd.buf; |
| argv[1] = NULL; |
| filter.argv = argv; |
| filter.use_shell = 1; |
| filter.in = -1; |
| |
| if (start_command(&filter) < 0) |
| die_errno(_("unable to start '%s' filter"), argv[0]); |
| close(1); |
| if (dup2(filter.in, 1) < 0) |
| die_errno(_("unable to redirect descriptor")); |
| close(filter.in); |
| |
| r = write_tar_archive(ar, args); |
| |
| close(1); |
| if (finish_command(&filter) != 0) |
| die(_("'%s' filter reported error"), argv[0]); |
| |
| strbuf_release(&cmd); |
| return r; |
| } |
| |
| static struct archiver tar_archiver = { |
| "tar", |
| write_tar_archive, |
| ARCHIVER_REMOTE |
| }; |
| |
| void init_tar_archiver(void) |
| { |
| int i; |
| register_archiver(&tar_archiver); |
| |
| tar_filter_config("tar.tgz.command", "gzip -cn", NULL); |
| tar_filter_config("tar.tgz.remote", "true", NULL); |
| tar_filter_config("tar.tar.gz.command", "gzip -cn", NULL); |
| tar_filter_config("tar.tar.gz.remote", "true", NULL); |
| git_config(git_tar_config, NULL); |
| for (i = 0; i < nr_tar_filters; i++) { |
| /* omit any filters that never had a command configured */ |
| if (tar_filters[i]->data) |
| register_archiver(tar_filters[i]); |
| } |
| } |