diff options
Diffstat (limited to 'src/ustar.c')
| -rw-r--r-- | src/ustar.c | 18 |
1 files changed, 18 insertions, 0 deletions
diff --git a/src/ustar.c b/src/ustar.c index 43292e9..cf1134a 100644 --- a/src/ustar.c +++ b/src/ustar.c @@ -81,22 +81,28 @@ _opkg_opk_ustar_next(struct opkg_opk_ustar *ustar, size_t i; char *header_uc; + /* Decompress next (hopefully valid header) record. */ switch (opkg_opk_gzip_read(ustar->gzip, header)) { case OPKG_OPK_OK: break; case OPKG_OPK_END: + /* End of gzip stream before end of ustar archive */ case OPKG_OPK_ERROR: return OPKG_OPK_ERROR; } + + /* Check for end of archive. */ memset(record, 0, OPKG_OPK_USTAR_RECORD_SIZE); if (memcmp(header, record, OPKG_OPK_USTAR_RECORD_SIZE) == 0) { return OPKG_OPK_END; } + /* Verify magic. */ if (memcmp(header->magic, "ustar", strlen("ustar")) != 0) { return OPKG_OPK_ERROR; } + /* Verify checksum. */ chksum_got = strtol(header->chksum, &end, OPKG_OPK_USTAR_NUM_BASE_); chksum_exp = 0; @@ -114,6 +120,7 @@ _opkg_opk_ustar_next(struct opkg_opk_ustar *ustar, return OPKG_OPK_ERROR; } + /* Depending on type, get size. */ switch (*header->typeflag) { case '0': /* Regular file */ case '7': /* High-performance or regular file */ @@ -147,15 +154,18 @@ opkg_opk_ustar_list(struct opkg_opk_ustar *ustar, int ret; char *end; + /* Get next header record, if any. */ if ((ret =_opkg_opk_ustar_next(ustar, &header)) != OPKG_OPK_OK) { return ret; /* Error or end of archive */ } + /* Allocate outward-facing member information structure. */ *member = malloc(sizeof(**member)); if (*member == NULL) { return OPKG_OPK_ERROR; } + /* Set name, mode, size, mtime, type, linkname, uname, and gname. */ if (header.prefix[0] != '\0') { sprintf((*member)->name, "%s/%s", header.prefix, header.name); } else { @@ -205,6 +215,7 @@ opkg_opk_ustar_list(struct opkg_opk_ustar *ustar, strncpy((*member)->uname, header.uname, sizeof((*member)->uname)); strncpy((*member)->gname, header.gname, sizeof((*member)->gname)); + /* Seek through data records until next header record. */ while (ustar->data_size_remaining > 0) { if (opkg_opk_ustar_read(ustar, NULL, NULL) == OPKG_OPK_ERROR) { free(*member); @@ -225,10 +236,12 @@ opkg_opk_ustar_seek(struct opkg_opk_ustar *ustar, int num_keys, ...) const char *member; for (;;) { + /* Get next header record. */ if (_opkg_opk_ustar_next(ustar, &header) != OPKG_OPK_OK) { return OPKG_OPK_ERROR; /* Error or end (not found) */ } + /* Prepare name (with prefix if any) for check. */ if (header.prefix[0] != '\0') { sprintf(name, "%s/%s", header.prefix, header.name); @@ -237,6 +250,7 @@ opkg_opk_ustar_seek(struct opkg_opk_ustar *ustar, int num_keys, ...) name[sizeof(header.name)] = '\0'; } + /* Check each requested name. */ va_start(ap, num_keys); for (key = 0; key < num_keys; ++key) { member = va_arg(ap, const char *); @@ -246,6 +260,7 @@ opkg_opk_ustar_seek(struct opkg_opk_ustar *ustar, int num_keys, ...) } va_end(ap); + /* Seek through data records until next header record. */ while (ustar->data_size_remaining > 0) { if (opkg_opk_ustar_read(ustar, NULL, NULL) == OPKG_OPK_ERROR) { @@ -264,6 +279,7 @@ opkg_opk_ustar_read(struct opkg_opk_ustar *ustar, char **buffer, size_t *size) return OPKG_OPK_END; } + /* Decompress next data record. */ switch (opkg_opk_gzip_read(ustar->gzip, ustar->read_record)) { case OPKG_OPK_OK: break; @@ -272,6 +288,8 @@ opkg_opk_ustar_read(struct opkg_opk_ustar *ustar, char **buffer, size_t *size) return OPKG_OPK_ERROR; } + /* Store buffer and size in caller's memory and update remaining size. + */ if (buffer != NULL) { *buffer = ustar->read_record; } |