diff options
Diffstat (limited to 'lib/libc/stdio/getdelim.c')
| -rw-r--r-- | lib/libc/stdio/getdelim.c | 158 |
1 files changed, 158 insertions, 0 deletions
diff --git a/lib/libc/stdio/getdelim.c b/lib/libc/stdio/getdelim.c new file mode 100644 index 0000000..fb02889 --- /dev/null +++ b/lib/libc/stdio/getdelim.c @@ -0,0 +1,158 @@ +/*- + * Copyright (c) 2009 David Schultz <das@FreeBSD.org> + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ + +#include <sys/cdefs.h> +__FBSDID("$FreeBSD$"); + +#include "namespace.h" +#include <sys/param.h> +#include <errno.h> +#include <limits.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include "un-namespace.h" + +#include "libc_private.h" +#include "local.h" + +static inline size_t +p2roundup(size_t n) +{ + + if (!powerof2(n)) { + n--; + n |= n >> 1; + n |= n >> 2; + n |= n >> 4; + n |= n >> 8; + n |= n >> 16; +#if SIZE_T_MAX > 0xffffffffU + n |= n >> 32; +#endif + n++; + } + return (n); +} + +/* + * Expand *linep to hold len bytes (up to SSIZE_MAX + 1). + */ +static inline int +expandtofit(char ** __restrict linep, size_t len, size_t * __restrict capp) +{ + char *newline; + size_t newcap; + + if (len > (size_t)SSIZE_MAX + 1) { + errno = EOVERFLOW; + return (-1); + } + if (len > *capp) { + if (len == (size_t)SSIZE_MAX + 1) /* avoid overflow */ + newcap = (size_t)SSIZE_MAX + 1; + else + newcap = p2roundup(len); + newline = realloc(*linep, newcap); + if (newline == NULL) + return (-1); + *capp = newcap; + *linep = newline; + } + return (0); +} + +/* + * Append the src buffer to the *dstp buffer. The buffers are of + * length srclen and *dstlenp, respectively, and dst has space for + * *dstlenp bytes. After the call, *dstlenp and *dstcapp are updated + * appropriately, and *dstp is reallocated if needed. Returns 0 on + * success, -1 on allocation failure. + */ +static int +sappend(char ** __restrict dstp, size_t * __restrict dstlenp, + size_t * __restrict dstcapp, char * __restrict src, size_t srclen) +{ + + /* ensure room for srclen + dstlen + terminating NUL */ + if (expandtofit(dstp, srclen + *dstlenp + 1, dstcapp)) + return (-1); + memcpy(*dstp + *dstlenp, src, srclen); + *dstlenp += srclen; + return (0); +} + +ssize_t +getdelim(char ** __restrict linep, size_t * __restrict linecapp, int delim, + FILE * __restrict fp) +{ + u_char *endp; + size_t linelen; + + FLOCKFILE(fp); + ORIENT(fp, -1); + + if (linep == NULL || linecapp == NULL) { + errno = EINVAL; + goto error; + } + + linelen = 0; + if (*linecapp == 0) + *linep = NULL; + + if (fp->_r <= 0 && __srefill(fp)) { + /* If fp is at EOF already, we just need space for the NUL. */ + if (__sferror(fp) || expandtofit(linep, 1, linecapp)) + goto error; + goto done; + } + + while ((endp = memchr(fp->_p, delim, fp->_r)) == NULL) { + if (sappend(linep, &linelen, linecapp, fp->_p, fp->_r)) + goto error; + if (__srefill(fp)) { + if (__sferror(fp)) + goto error; + goto done; /* hit EOF */ + } + } + endp++; /* snarf the delimiter, too */ + if (sappend(linep, &linelen, linecapp, fp->_p, endp - fp->_p)) + goto error; + fp->_r -= endp - fp->_p; + fp->_p = endp; +done: + /* Invariant: *linep has space for at least linelen+1 bytes. */ + (*linep)[linelen] = '\0'; + FUNLOCKFILE(fp); + return (linelen); + +error: + fp->_flags |= __SERR; + FUNLOCKFILE(fp); + return (-1); +} |
