#include "stdio_impl.h"
+#include <errno.h>
+#include <limits.h>
+#include <string.h>
+#include <stdlib.h>
+#include "libc.h"
struct cookie {
char **bufp;
size_t space;
};
+struct ms_FILE {
+ FILE f;
+ struct cookie c;
+ unsigned char buf[BUFSIZ];
+};
+
static off_t ms_seek(FILE *f, off_t off, int whence)
{
ssize_t base;
struct cookie *c = f->cookie;
- switch (whence) {
- case SEEK_SET:
- base = 0;
- break;
- case SEEK_CUR:
- base = c->pos;
- break;
- case SEEK_END:
- base = c->len;
- break;
- default:
- fail:
+ if (whence>2U) {
+fail:
errno = EINVAL;
return -1;
}
- if (-off > base || off > SSIZE_MAX-base) goto fail;
+ base = (size_t [3]){0, c->pos, c->len}[whence];
+ if (off < -base || off > SSIZE_MAX-base) goto fail;
return c->pos = base+off;
}
f->wpos = f->wbase;
if (ms_write(f, f->wbase, len2) < len2) return 0;
}
- if (len > c->space - c->pos) {
- len2 = 2*c->space+1 | c->space+len+1;
+ if (len + c->pos >= c->space) {
+ len2 = 2*c->space+1 | c->pos+len+1;
newbuf = realloc(c->buf, len2);
if (!newbuf) return 0;
*c->bufp = c->buf = newbuf;
FILE *open_memstream(char **bufp, size_t *sizep)
{
- FILE *f;
- struct cookie *c;
- if (!(f=malloc(sizeof *f + sizeof *c + BUFSIZ))) return 0;
- memset(f, 0, sizeof *f + sizeof *c);
- f->cookie = c = (void *)(f+1);
+ struct ms_FILE *f;
+ char *buf;
- c->bufp = bufp;
- c->sizep = sizep;
- c->pos = c->len = c->space = 0;
- c->buf = 0;
+ if (!(f=malloc(sizeof *f))) return 0;
+ if (!(buf=malloc(sizeof *buf))) {
+ free(f);
+ return 0;
+ }
+ memset(&f->f, 0, sizeof f->f);
+ memset(&f->c, 0, sizeof f->c);
+ f->f.cookie = &f->c;
- f->flags = F_NORD;
- f->fd = -1;
- f->buf = (void *)(c+1);
- f->buf_size = BUFSIZ;
- f->lbf = EOF;
- f->write = ms_write;
- f->seek = ms_seek;
- f->close = ms_close;
+ f->c.bufp = bufp;
+ f->c.sizep = sizep;
+ f->c.pos = f->c.len = f->c.space = *sizep = 0;
+ f->c.buf = *bufp = buf;
+ *buf = 0;
- if (!libc.threaded) {
- f->lock = -1;
- f->next = libc.ofl_head;
- if (libc.ofl_head) libc.ofl_head->prev = f;
- libc.ofl_head = f;
- }
+ f->f.flags = F_NORD;
+ f->f.fd = -1;
+ f->f.buf = f->buf;
+ f->f.buf_size = sizeof f->buf;
+ f->f.lbf = EOF;
+ f->f.write = ms_write;
+ f->f.seek = ms_seek;
+ f->f.close = ms_close;
+ f->f.mode = -1;
+
+ if (!libc.threaded) f->f.lock = -1;
- return f;
+ return __ofl_add(&f->f);
}