diff options
author | Patrick Steinhardt <ps@pks.im> | 2023-06-06 08:19:37 +0300 |
---|---|---|
committer | Junio C Hamano <gitster@pobox.com> | 2023-06-12 23:23:24 +0300 |
commit | af35e56b0f83f872a8d82d8293fae87c80b491ef (patch) | |
tree | 504a29c18dde8f8c85332d7f7b7c3820d4d0cb57 | |
parent | b116c77307853a9fa8f74d1ad16bed98a7211207 (diff) |
strbuf: provide CRLF-aware helper to read until a specified delimiter
Many of our commands support reading input that is separated either via
newlines or via NUL characters. Furthermore, in order to be a better
cross platform citizen, these commands typically know to strip the CRLF
sequence so that we also support reading newline-separated inputs on
e.g. the Windows platform. This results in the following kind of awkward
pattern:
```
struct strbuf input = STRBUF_INIT;
while (1) {
int ret;
if (nul_terminated)
ret = strbuf_getline_nul(&input, stdin);
else
ret = strbuf_getline(&input, stdin);
if (ret)
break;
...
}
```
Introduce a new CRLF-aware helper function that can read up to a user
specified delimiter. If the delimiter is `\n` the function knows to also
strip CRLF, otherwise it will only strip the specified delimiter. This
results in the following, much more readable code pattern:
```
struct strbuf input = STRBUF_INIT;
while (strbuf_getdelim_strip_crlf(&input, stdin, delim) != EOF) {
...
}
```
The new function will be used in a subsequent commit.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
-rw-r--r-- | strbuf.c | 11 | ||||
-rw-r--r-- | strbuf.h | 12 |
2 files changed, 20 insertions, 3 deletions
@@ -721,11 +721,11 @@ static int strbuf_getdelim(struct strbuf *sb, FILE *fp, int term) return 0; } -int strbuf_getline(struct strbuf *sb, FILE *fp) +int strbuf_getdelim_strip_crlf(struct strbuf *sb, FILE *fp, int term) { - if (strbuf_getwholeline(sb, fp, '\n')) + if (strbuf_getwholeline(sb, fp, term)) return EOF; - if (sb->buf[sb->len - 1] == '\n') { + if (term == '\n' && sb->buf[sb->len - 1] == '\n') { strbuf_setlen(sb, sb->len - 1); if (sb->len && sb->buf[sb->len - 1] == '\r') strbuf_setlen(sb, sb->len - 1); @@ -733,6 +733,11 @@ int strbuf_getline(struct strbuf *sb, FILE *fp) return 0; } +int strbuf_getline(struct strbuf *sb, FILE *fp) +{ + return strbuf_getdelim_strip_crlf(sb, fp, '\n'); +} + int strbuf_getline_lf(struct strbuf *sb, FILE *fp) { return strbuf_getdelim(sb, fp, '\n'); @@ -476,6 +476,18 @@ int strbuf_readlink(struct strbuf *sb, const char *path, size_t hint); ssize_t strbuf_write(struct strbuf *sb, FILE *stream); /** + * Read from a FILE * until the specified terminator is encountered, + * overwriting the existing contents of the strbuf. + * + * Reading stops after the terminator or at EOF. The terminator is + * removed from the buffer before returning. If the terminator is LF + * and if it is preceded by a CR, then the whole CRLF is stripped. + * Returns 0 unless there was nothing left before EOF, in which case + * it returns `EOF`. + */ +int strbuf_getdelim_strip_crlf(struct strbuf *sb, FILE *fp, int term); + +/** * Read a line from a FILE *, overwriting the existing contents of * the strbuf. The strbuf_getline*() family of functions share * this signature, but have different line termination conventions. |