[PATCH 2/4] mailinfo: simplify parsing of header values
- From
Jeff King <peff@peff.net>
- Date
- Feb 11, 2020, 17:19 UTC
- Message-ID
- <20200211171923.GB2119034@coredump.intra.peff.net>
- In-Reply-To
- <20200211171649.GB2118476@coredump.intra.peff.net>
Our code to parse header values first checks to see if a line starts with a header, and then manually skips past the matched string to find the value. We can do this all in one step by modeling after skip_prefix(), which returns a pointer into the string after the parsing.
This lets us remove some repeated strings, and will also enable us to parse more flexibly in a future patch.
Signed-off-by: Jeff King <peff@peff.net> --- mailinfo.c | 40 ++++++++++++++++++++++------------------ 1 file changed, 22 insertions(+), 18 deletions(-)
diff --git a/mailinfo.c b/mailinfo.c index 59d5a8b8f3..ee8d05e239 100644 --- a/mailinfo.c +++ b/mailinfo.c @@ -346,11 +346,16 @@ static const char *header[MAX_HDR_PARSED] = { "From","Subject","Date", }; -static inline int cmp_header(const struct strbuf *line, const char *hdr) +static inline int skip_header(const struct strbuf *line, const char *hdr, + const char **outval) { - int len = strlen(hdr); - return !strncasecmp(line->buf, hdr, len) && line->len > len && - line->buf[len] == ':' && isspace(line->buf[len + 1]); + const char *val; + if (!skip_iprefix(line->buf, hdr, &val) || + *val++ != ':' || + !isspace(*val++)) + return 0; + *outval = val; + return 1; } static int is_format_patch_separator(const char *line, int len) @@ -547,17 +552,18 @@ static int check_header(struct mailinfo *mi, const struct strbuf *line, struct strbuf *hdr_data[], int overwrite) { - int i, ret = 0, len; + int i, ret = 0; struct strbuf sb = STRBUF_INIT; + const char *val; /* search for the interesting parts */ for (i = 0; header[i]; i++) { - int len = strlen(header[i]); - if ((!hdr_data[i] || overwrite) && cmp_header(line, header[i])) { + if ((!hdr_data[i] || overwrite) && + skip_header(line, header[i], &val)) { /* Unwrap inline B and Q encoding, and optionally * normalize the meta information to utf8. */ - strbuf_addstr(&sb, line->buf + len + 2); + strbuf_addstr(&sb, val); decode_header(mi, &sb); handle_header(&hdr_data[i], &sb); ret = 1; @@ -566,25 +572,22 @@ static int check_header(struct mailinfo *mi, } /* Content stuff */ - if (cmp_header(line, "Content-Type")) { - len = strlen("Content-Type: "); - strbuf_addstr(&sb, line->buf + len); + if (skip_header(line, "Content-Type", &val)) { + strbuf_addstr(&sb, val); decode_header(mi, &sb); handle_content_type(mi, &sb); ret = 1; goto check_header_out; } - if (cmp_header(line, "Content-Transfer-Encoding")) { - len = strlen("Content-Transfer-Encoding: "); - strbuf_addstr(&sb, line->buf + len); + if (skip_header(line, "Content-Transfer-Encoding", &val)) { + strbuf_addstr(&sb, val); decode_header(mi, &sb); handle_content_transfer_encoding(mi, &sb); ret = 1; goto check_header_out; } - if (cmp_header(line, "Message-Id")) { - len = strlen("Message-Id: "); - strbuf_addstr(&sb, line->buf + len); + if (skip_header(line, "Message-Id", &val)) { + strbuf_addstr(&sb, val); decode_header(mi, &sb); if (mi->add_message_id) mi->message_id = strbuf_detach(&sb, NULL); @@ -606,8 +609,9 @@ static int is_inbody_header(const struct mailinfo *mi, const struct strbuf *line) { int i; + const char *val; for (i = 0; header[i]; i++) - if (!mi->s_hdr_data[i] && cmp_header(line, header[i])) + if (!mi->s_hdr_data[i] && skip_header(line, header[i], &val)) return 1; return 0; }
-- 2.25.0.708.g4c6f45973e