diff options
Diffstat (limited to 'libc/upstream-openbsd/lib/libc/stdio/vasprintf.c')
| -rw-r--r-- | libc/upstream-openbsd/lib/libc/stdio/vasprintf.c | 27 |
1 files changed, 18 insertions, 9 deletions
diff --git a/libc/upstream-openbsd/lib/libc/stdio/vasprintf.c b/libc/upstream-openbsd/lib/libc/stdio/vasprintf.c index 98cdb4554..c2e17e7c1 100644 --- a/libc/upstream-openbsd/lib/libc/stdio/vasprintf.c +++ b/libc/upstream-openbsd/lib/libc/stdio/vasprintf.c @@ -1,7 +1,7 @@ -/* $OpenBSD: vasprintf.c,v 1.19 2015/12/28 22:08:18 mmcc Exp $ */ +/* $OpenBSD: vasprintf.c,v 1.23 2019/01/25 00:19:25 millert Exp $ */ /* - * Copyright (c) 1997 Todd C. Miller <Todd.Miller@courtesan.com> + * Copyright (c) 1997 Todd C. Miller <millert@openbsd.org> * * Permission to use, copy, modify, and distribute this software for any * purpose with or without fee is hereby granted, provided that the above @@ -20,31 +20,40 @@ #include <stdlib.h> #include <string.h> #include <errno.h> +#include <unistd.h> #include "local.h" +#define INITIAL_SIZE 128 + int vasprintf(char **str, const char *fmt, __va_list ap) { int ret; FILE f; struct __sfileext fext; - unsigned char *_base; + const int pgsz = getpagesize(); _FILEEXT_SETUP(&f, &fext); f._file = -1; f._flags = __SWR | __SSTR | __SALC; - f._bf._base = f._p = malloc(128); + f._bf._base = f._p = malloc(INITIAL_SIZE); if (f._bf._base == NULL) goto err; - f._bf._size = f._w = 127; /* Leave room for the NUL */ + f._bf._size = f._w = INITIAL_SIZE - 1; /* leave room for the NUL */ ret = __vfprintf(&f, fmt, ap); if (ret == -1) goto err; *f._p = '\0'; - _base = realloc(f._bf._base, ret + 1); - if (_base == NULL) - goto err; - *str = (char *)_base; + if (ret + 1 > INITIAL_SIZE && ret + 1 < pgsz / 2) { + /* midsize allocations can try to conserve memory */ + unsigned char *_base = recallocarray(f._bf._base, + f._bf._size + 1, ret + 1, 1); + + if (_base == NULL) + goto err; + *str = (char *)_base; + } else + *str = (char *)f._bf._base; return (ret); err: |