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| /* | |
| * 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) { | |
| CALLOC_ARRAY(ar, 1); | |
| 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]); | |
| } | |
| } |