diff options
| -rw-r--r-- | builtin-apply.c | 206 |
1 files changed, 141 insertions, 65 deletions
diff --git a/builtin-apply.c b/builtin-apply.c index 267aab0e8..4573c9abb 100644 --- a/builtin-apply.c +++ b/builtin-apply.c @@ -109,6 +109,13 @@ static int max_change, max_len; */ static int linenr = 1; +/* + * This represents one "hunk" from a patch, starting with + * "@@ -oldpos,oldlines +newpos,newlines @@" marker. The + * patch text is pointed at by patch, and its byte length + * is stored in size. leading and trailing are the number + * of context lines. + */ struct fragment { unsigned long leading, trailing; unsigned long oldpos, oldlines; @@ -118,12 +125,19 @@ struct fragment { struct fragment *next; }; +/* + * When dealing with a binary patch, we reuse "leading" field + * to store the type of the binary hunk, either deflated "delta" + * or deflated "literal". + */ +#define binary_patch_method leading +#define BINARY_DELTA_DEFLATED 1 +#define BINARY_LITERAL_DEFLATED 2 + struct patch { char *new_name, *old_name, *def_name; unsigned int old_mode, new_mode; int is_rename, is_copy, is_new, is_delete, is_binary; -#define BINARY_DELTA_DEFLATED 1 -#define BINARY_LITERAL_DEFLATED 2 unsigned long deflate_origlen; int lines_added, lines_deleted; int score; @@ -979,43 +993,70 @@ static inline int metadata_changes(struct patch *patch) patch->old_mode != patch->new_mode); } -static int parse_binary(char *buffer, unsigned long size, struct patch *patch) +static char *inflate_it(const void *data, unsigned long size, + unsigned long inflated_size) { - /* We have read "GIT binary patch\n"; what follows is a line - * that says the patch method (currently, either "deflated - * literal" or "deflated delta") and the length of data before - * deflating; a sequence of 'length-byte' followed by base-85 - * encoded data follows. + z_stream stream; + void *out; + int st; + + memset(&stream, 0, sizeof(stream)); + + stream.next_in = (unsigned char *)data; + stream.avail_in = size; + stream.next_out = out = xmalloc(inflated_size); + stream.avail_out = inflated_size; + inflateInit(&stream); + st = inflate(&stream, Z_FINISH); + if ((st != Z_STREAM_END) || stream.total_out != inflated_size) { + free(out); + return NULL; + } + return out; +} + +static struct fragment *parse_binary_hunk(char **buf_p, + unsigned long *sz_p, + int *status_p, + int *used_p) +{ + /* Expect a line that begins with binary patch method ("literal" + * or "delta"), followed by the length of data before deflating. + * a sequence of 'length-byte' followed by base-85 encoded data + * should follow, terminated by a newline. * * Each 5-byte sequence of base-85 encodes up to 4 bytes, * and we would limit the patch line to 66 characters, * so one line can fit up to 13 groups that would decode * to 52 bytes max. The length byte 'A'-'Z' corresponds * to 1-26 bytes, and 'a'-'z' corresponds to 27-52 bytes. - * The end of binary is signaled with an empty line. */ int llen, used; - struct fragment *fragment; + unsigned long size = *sz_p; + char *buffer = *buf_p; + int patch_method; + unsigned long origlen; char *data = NULL; + int hunk_size = 0; + struct fragment *frag; - patch->fragments = fragment = xcalloc(1, sizeof(*fragment)); - - /* Grab the type of patch */ llen = linelen(buffer, size); used = llen; - linenr++; + + *status_p = 0; if (!strncmp(buffer, "delta ", 6)) { - patch->is_binary = BINARY_DELTA_DEFLATED; - patch->deflate_origlen = strtoul(buffer + 6, NULL, 10); + patch_method = BINARY_DELTA_DEFLATED; + origlen = strtoul(buffer + 6, NULL, 10); } else if (!strncmp(buffer, "literal ", 8)) { - patch->is_binary = BINARY_LITERAL_DEFLATED; - patch->deflate_origlen = strtoul(buffer + 8, NULL, 10); + patch_method = BINARY_LITERAL_DEFLATED; + origlen = strtoul(buffer + 8, NULL, 10); } else - return error("unrecognized binary patch at line %d: %.*s", - linenr-1, llen-1, buffer); + return NULL; + + linenr++; buffer += llen; while (1) { int byte_length, max_byte_length, newsize; @@ -1044,21 +1085,79 @@ static int parse_binary(char *buffer, unsigned long size, struct patch *patch) if (max_byte_length < byte_length || byte_length <= max_byte_length - 4) goto corrupt; - newsize = fragment->size + byte_length; + newsize = hunk_size + byte_length; data = xrealloc(data, newsize); - if (decode_85(data + fragment->size, - buffer + 1, - byte_length)) + if (decode_85(data + hunk_size, buffer + 1, byte_length)) goto corrupt; - fragment->size = newsize; + hunk_size = newsize; buffer += llen; size -= llen; } - fragment->patch = data; - return used; + + frag = xcalloc(1, sizeof(*frag)); + frag->patch = inflate_it(data, hunk_size, origlen); + if (!frag->patch) + goto corrupt; + free(data); + frag->size = origlen; + *buf_p = buffer; + *sz_p = size; + *used_p = used; + frag->binary_patch_method = patch_method; + return frag; + corrupt: - return error("corrupt binary patch at line %d: %.*s", - linenr-1, llen-1, buffer); + if (data) + free(data); + *status_p = -1; + error("corrupt binary patch at line %d: %.*s", + linenr-1, llen-1, buffer); + return NULL; +} + +static int parse_binary(char *buffer, unsigned long size, struct patch *patch) +{ + /* We have read "GIT binary patch\n"; what follows is a line + * that says the patch method (currently, either "literal" or + * "delta") and the length of data before deflating; a + * sequence of 'length-byte' followed by base-85 encoded data + * follows. + * + * When a binary patch is reversible, there is another binary + * hunk in the same format, starting with patch method (either + * "literal" or "delta") with the length of data, and a sequence + * of length-byte + base-85 encoded data, terminated with another + * empty line. This data, when applied to the postimage, produces + * the preimage. + */ + struct fragment *forward; + struct fragment *reverse; + int status; + int used, used_1; + + forward = parse_binary_hunk(&buffer, &size, &status, &used); + if (!forward && !status) + /* there has to be one hunk (forward hunk) */ + return error("unrecognized binary patch at line %d", linenr-1); + if (status) + /* otherwise we already gave an error message */ + return status; + + reverse = parse_binary_hunk(&buffer, &size, &status, &used_1); + if (reverse) + used += used_1; + else if (status) { + /* not having reverse hunk is not an error, but having + * a corrupt reverse hunk is. + */ + free((void*) forward->patch); + free(forward); + return status; + } + forward->next = reverse; + patch->fragments = forward; + patch->is_binary = 1; + return used; } static int parse_chunk(char *buffer, unsigned long size, struct patch *patch) @@ -1505,28 +1604,6 @@ static int apply_one_fragment(struct buffer_desc *desc, struct fragment *frag, i return offset; } -static char *inflate_it(const void *data, unsigned long size, - unsigned long inflated_size) -{ - z_stream stream; - void *out; - int st; - - memset(&stream, 0, sizeof(stream)); - - stream.next_in = (unsigned char *)data; - stream.avail_in = size; - stream.next_out = out = xmalloc(inflated_size); - stream.avail_out = inflated_size; - inflateInit(&stream); - st = inflate(&stream, Z_FINISH); - if ((st != Z_STREAM_END) || stream.total_out != inflated_size) { - free(out); - return NULL; - } - return out; -} - static int apply_binary_fragment(struct buffer_desc *desc, struct patch *patch) { unsigned long dst_size; @@ -1534,30 +1611,29 @@ static int apply_binary_fragment(struct buffer_desc *desc, struct patch *patch) void *data; void *result; - /* Binary patch is irreversible */ - if (apply_in_reverse) - return error("cannot reverse-apply a binary patch to '%s'", - patch->new_name - ? patch->new_name : patch->old_name); - - data = inflate_it(fragment->patch, fragment->size, - patch->deflate_origlen); - if (!data) - return error("corrupt patch data"); - switch (patch->is_binary) { + /* Binary patch is irreversible without the optional second hunk */ + if (apply_in_reverse) { + if (!fragment->next) + return error("cannot reverse-apply a binary patch " + "without the reverse hunk to '%s'", + patch->new_name + ? patch->new_name : patch->old_name); + fragment = fragment; + } + data = (void*) fragment->patch; + switch (fragment->binary_patch_method) { case BINARY_DELTA_DEFLATED: result = patch_delta(desc->buffer, desc->size, data, - patch->deflate_origlen, + fragment->size, &dst_size); free(desc->buffer); desc->buffer = result; - free(data); break; case BINARY_LITERAL_DEFLATED: free(desc->buffer); desc->buffer = data; - dst_size = patch->deflate_origlen; + dst_size = fragment->size; break; } if (!desc->buffer) |