From 617182734ca0beffa347747019d78b972e2038f9 Mon Sep 17 00:00:00 2001 From: Rich Felker Date: Sat, 11 Aug 2012 18:10:38 -0400 Subject: [PATCH] add bsd fgetln function optimized to avoid allocation and return lines directly out of the stream buffer whenever possible. --- include/stdio.h | 4 ++++ src/internal/stdio_impl.h | 2 +- src/stdio/fclose.c | 1 + src/stdio/fgetln.c | 19 +++++++++++++++++++ 4 files changed, 25 insertions(+), 1 deletion(-) create mode 100644 src/stdio/fgetln.c diff --git a/include/stdio.h b/include/stdio.h index 3d22220f..19ab8bcd 100644 --- a/include/stdio.h +++ b/include/stdio.h @@ -172,6 +172,10 @@ int getw(FILE *); int putw(int, FILE *); #endif +#ifdef _BSD_SOURCE +char *fgetln(FILE *, size_t *); +#endif + #ifdef _GNU_SOURCE int asprintf(char **, const char *, ...); int vasprintf(char **, const char *, va_list); diff --git a/src/internal/stdio_impl.h b/src/internal/stdio_impl.h index d54c918b..65dcfbda 100644 --- a/src/internal/stdio_impl.h +++ b/src/internal/stdio_impl.h @@ -57,7 +57,7 @@ struct __FILE_s { int waiters; void *cookie; off_t off; - void *dummy4; + char *getln_buf; void *mustbezero_2; unsigned char *shend; off_t shlim, shcnt; diff --git a/src/stdio/fclose.c b/src/stdio/fclose.c index 373a2c76..8fdc3f7d 100644 --- a/src/stdio/fclose.c +++ b/src/stdio/fclose.c @@ -16,6 +16,7 @@ int fclose(FILE *f) r = fflush(f); r |= f->close(f); + if (f->getln_buf) free(f->getln_buf); if (!perm) free(f); return r; diff --git a/src/stdio/fgetln.c b/src/stdio/fgetln.c new file mode 100644 index 00000000..06b88837 --- /dev/null +++ b/src/stdio/fgetln.c @@ -0,0 +1,19 @@ +#include "stdio_impl.h" + +char *fgetln(FILE *f, size_t *plen) +{ + char *ret = 0, *z; + ssize_t l; + FLOCK(f); + ungetc(getc_unlocked(f), f); + if ((z=memchr(f->rpos, '\n', f->rend - f->rpos))) { + ret = (char *)f->rpos; + *plen = ++z - ret; + f->rpos = (void *)z; + } else if ((l = getline(&f->getln_buf, (size_t[]){0}, f)) > 0) { + *plen = l; + ret = f->getln_buf; + } + FUNLOCK(f); + return ret; +} -- 2.25.1