From fe6eb7f2c506190c817407accf27834005a57f2b Mon Sep 17 00:00:00 2001 From: Jeff King Date: Wed, 27 Aug 2014 03:56:01 -0400 Subject: [PATCH] commit: provide a function to find a header in a buffer Usually when we parse a commit, we read it line by line and handle each individual line (e.g., parse_commit and parse_commit_header). Sometimes, however, we only care about extracting a single header. Code in this situation is stuck doing an ad-hoc parse of the commit buffer. Let's provide a reusable function to locate a header within the commit. The code is modeled after pretty.c's get_header, which is used to extract the encoding. Since some callers may not have the "struct commit" to go along with the buffer, we drop that parameter. The only thing lost is a warning for truncated commits, but that's OK. This shouldn't happen in practice, and even if it does, there's no particular reason that this function needs to complain about it. It either finds the header it was asked for, or it doesn't (and in the latter case, the caller will typically complain). Signed-off-by: Jeff King Signed-off-by: Junio C Hamano --- commit.c | 22 ++++++++++++++++++++++ commit.h | 11 +++++++++++ pretty.c | 33 ++++++--------------------------- 3 files changed, 39 insertions(+), 27 deletions(-) diff --git a/commit.c b/commit.c index ae7f2b10f4..b6ffd623c8 100644 --- a/commit.c +++ b/commit.c @@ -1660,3 +1660,25 @@ void print_commit_list(struct commit_list *list, printf(format, sha1_to_hex(list->item->object.sha1)); } } + +const char *find_commit_header(const char *msg, const char *key, size_t *out_len) +{ + int key_len = strlen(key); + const char *line = msg; + + while (line) { + const char *eol = strchrnul(line, '\n'); + + if (line == eol) + return NULL; + + if (eol - line > key_len && + !strncmp(line, key, key_len) && + line[key_len] == ' ') { + *out_len = eol - line - key_len - 1; + return line + key_len + 1; + } + line = *eol ? eol + 1 : NULL; + } + return NULL; +} diff --git a/commit.h b/commit.h index a8cbf52f15..12f4fe10c1 100644 --- a/commit.h +++ b/commit.h @@ -313,6 +313,17 @@ extern struct commit_extra_header *read_commit_extra_headers(struct commit *, co extern void free_commit_extra_headers(struct commit_extra_header *extra); +/* + * Search the commit object contents given by "msg" for the header "key". + * Returns a pointer to the start of the header contents, or NULL. The length + * of the header, up to the first newline, is returned via out_len. + * + * Note that some headers (like mergetag) may be multi-line. It is the caller's + * responsibility to parse further in this case! + */ +extern const char *find_commit_header(const char *msg, const char *key, + size_t *out_len); + typedef void (*each_mergetag_fn)(struct commit *commit, struct commit_extra_header *extra, void *cb_data); diff --git a/pretty.c b/pretty.c index 3a1da6fd32..3a705576f3 100644 --- a/pretty.c +++ b/pretty.c @@ -547,31 +547,11 @@ static void add_merge_info(const struct pretty_print_context *pp, strbuf_addch(sb, '\n'); } -static char *get_header(const struct commit *commit, const char *msg, - const char *key) +static char *get_header(const char *msg, const char *key) { - int key_len = strlen(key); - const char *line = msg; - - while (line) { - const char *eol = strchrnul(line, '\n'), *next; - - if (line == eol) - return NULL; - if (!*eol) { - warning("malformed commit (header is missing newline): %s", - sha1_to_hex(commit->object.sha1)); - next = NULL; - } else - next = eol + 1; - if (eol - line > key_len && - !strncmp(line, key, key_len) && - line[key_len] == ' ') { - return xmemdupz(line + key_len + 1, eol - line - key_len - 1); - } - line = next; - } - return NULL; + size_t len; + const char *v = find_commit_header(msg, key, &len); + return v ? xmemdupz(v, len) : NULL; } static char *replace_encoding_header(char *buf, const char *encoding) @@ -617,11 +597,10 @@ const char *logmsg_reencode(const struct commit *commit, if (!output_encoding || !*output_encoding) { if (commit_encoding) - *commit_encoding = - get_header(commit, msg, "encoding"); + *commit_encoding = get_header(msg, "encoding"); return msg; } - encoding = get_header(commit, msg, "encoding"); + encoding = get_header(msg, "encoding"); if (commit_encoding) *commit_encoding = encoding; use_encoding = encoding ? encoding : utf8;