diff options
Diffstat (limited to 'libc/upstream-openbsd/lib/libc/stdio/fmemopen.c')
| -rw-r--r-- | libc/upstream-openbsd/lib/libc/stdio/fmemopen.c | 183 |
1 files changed, 183 insertions, 0 deletions
diff --git a/libc/upstream-openbsd/lib/libc/stdio/fmemopen.c b/libc/upstream-openbsd/lib/libc/stdio/fmemopen.c new file mode 100644 index 000000000..8cda04763 --- /dev/null +++ b/libc/upstream-openbsd/lib/libc/stdio/fmemopen.c @@ -0,0 +1,183 @@ +/* $OpenBSD: fmemopen.c,v 1.2 2013/03/27 15:06:25 mpi Exp $ */ + +/* + * Copyright (c) 2011 Martin Pieuchot <mpi@openbsd.org> + * Copyright (c) 2009 Ted Unangst + * + * Permission to use, copy, modify, and distribute this software for any + * purpose with or without fee is hereby granted, provided that the above + * copyright notice and this permission notice appear in all copies. + * + * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES + * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR + * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES + * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN + * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF + * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. + */ + +#include <errno.h> +#include <fcntl.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include "local.h" + +struct state { + char *string; /* actual stream */ + size_t pos; /* current position */ + size_t size; /* allocated size */ + size_t len; /* length of the data */ + int update; /* open for update */ +}; + +static int +fmemopen_read(void *v, char *b, int l) +{ + struct state *st = v; + int i; + + for (i = 0; i < l && i + st->pos < st->len; i++) + b[i] = st->string[st->pos + i]; + st->pos += i; + + return (i); +} + +static int +fmemopen_write(void *v, const char *b, int l) +{ + struct state *st = v; + int i; + + for (i = 0; i < l && i + st->pos < st->size; i++) + st->string[st->pos + i] = b[i]; + st->pos += i; + + if (st->pos >= st->len) { + st->len = st->pos; + + if (st->len < st->size) + st->string[st->len] = '\0'; + else if (!st->update) + st->string[st->size - 1] = '\0'; + } + + return (i); +} + +static fpos_t +fmemopen_seek(void *v, fpos_t off, int whence) +{ + struct state *st = v; + ssize_t base = 0; + + switch (whence) { + case SEEK_SET: + break; + case SEEK_CUR: + base = st->pos; + break; + case SEEK_END: + base = st->len; + break; + } + + if (off > st->size - base || off < -base) { + errno = EOVERFLOW; + return (-1); + } + + st->pos = base + off; + + return (st->pos); +} + +static int +fmemopen_close(void *v) +{ + free(v); + + return (0); +} + +static int +fmemopen_close_free(void *v) +{ + struct state *st = v; + + free(st->string); + free(st); + + return (0); +} + +FILE * +fmemopen(void *buf, size_t size, const char *mode) +{ + struct state *st; + FILE *fp; + int flags, oflags; + + if (size == 0) { + errno = EINVAL; + return (NULL); + } + + if ((flags = __sflags(mode, &oflags)) == 0) { + errno = EINVAL; + return (NULL); + } + + if (buf == NULL && ((oflags & O_RDWR) == 0)) { + errno = EINVAL; + return (NULL); + } + + if ((st = malloc(sizeof(*st))) == NULL) + return (NULL); + + if ((fp = __sfp()) == NULL) { + free(st); + return (NULL); + } + + st->pos = 0; + st->len = (oflags & O_WRONLY) ? 0 : size; + st->size = size; + st->update = oflags & O_RDWR; + + if (buf == NULL) { + if ((st->string = malloc(size)) == NULL) { + free(st); + fp->_flags = 0; + return (NULL); + } + *st->string = '\0'; + } else { + st->string = (char *)buf; + + if (oflags & O_TRUNC) + *st->string = '\0'; + + if (oflags & O_APPEND) { + char *p; + + if ((p = memchr(st->string, '\0', size)) != NULL) + st->pos = st->len = (p - st->string); + else + st->pos = st->len = size; + } + } + + fp->_flags = (short)flags; + fp->_file = -1; + fp->_cookie = (void *)st; + fp->_read = (flags & __SWR) ? NULL : fmemopen_read; + fp->_write = (flags & __SRD) ? NULL : fmemopen_write; + fp->_seek = fmemopen_seek; + fp->_close = (buf == NULL) ? fmemopen_close_free : fmemopen_close; + + return (fp); +} |