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-rw-r--r--src/stdio/fmemopen.c84
1 files changed, 66 insertions, 18 deletions
diff --git a/src/stdio/fmemopen.c b/src/stdio/fmemopen.c
index cc72a420..f518528f 100644
--- a/src/stdio/fmemopen.c
+++ b/src/stdio/fmemopen.c
@@ -1,32 +1,69 @@
-#if 0
#include "stdio_impl.h"
-static ssize_t mread(FILE *f, unsigned char *buf, size_t len)
+struct cookie {
+ size_t pos, len, size;
+ unsigned char *buf;
+ int mode;
+};
+
+static off_t mseek(FILE *f, off_t off, int whence)
{
- size_t rem = f->memsize - f->mempos;
+ ssize_t base;
+ struct cookie *c = f->cookie;
+ if (whence>2U) {
+fail:
+ errno = EINVAL;
+ return -1;
+ }
+ base = (size_t [3]){0, c->pos, c->len}[whence];
+ if (off < -base || off > SSIZE_MAX-base) goto fail;
+ return c->pos = base+off;
+}
+
+static size_t mread(FILE *f, unsigned char *buf, size_t len)
+{
+ struct cookie *c = f->cookie;
+ size_t rem = c->size - c->pos;
if (len > rem) len = rem;
- memcpy(buf, f->membuf+f->mempos, len);
- f->mempos += len;
+ memcpy(buf, c->buf+c->pos, len);
+ c->pos += len;
+ rem -= len;
+ if (rem > f->buf_size) rem = f->buf_size;
+ f->rpos = f->buf;
+ f->rend = f->buf + rem;
+ memcpy(f->rpos, c->buf+c->pos, rem);
+ if (!len) f->flags |= F_EOF;
return len;
}
-static ssize_t mwrite(FILE *f, const unsigned char *buf, size_t len)
+static size_t mwrite(FILE *f, const unsigned char *buf, size_t len)
{
+ struct cookie *c = f->cookie;
size_t rem;
- if (f->memmode == 'a') f->mempos = f->memsize;
- rem = f->memlim - f->mempos;
- if (len > rem) len = rem;
- memcpy(f->membuf+f->mempos, buf, len);
- f->mempos += len;
- if (f->mempos >= f->memsize) {
- f->memsize = f->mempos;
+ size_t len2 = f->wpos - f->wbase;
+ if (len2) {
+ f->wpos = f->wbase;
+ if (mwrite(f, f->wpos, len2) < len2) return 0;
}
+ if (c->mode == 'a') c->pos = c->size;
+ rem = c->size - c->pos;
+ if (len > rem) len = rem;
+ memcpy(c->buf+c->pos, buf, len);
+ c->pos += len;
+ if (c->pos >= c->len) c->len = c->pos;
+ c->buf[c->len==c->size ? c->len-1 : c->len] = 0;
return len;
}
+static int mclose(FILE *m)
+{
+ return 0;
+}
+
FILE *fmemopen(void *buf, size_t size, const char *mode)
{
FILE *f;
+ struct cookie *c;
int plus = !!strchr(mode, '+');
if (!size || !strchr("rwa", *mode)) {
@@ -39,23 +76,34 @@ FILE *fmemopen(void *buf, size_t size, const char *mode)
return 0;
}
- f = calloc(sizeof(FILE) + UNGET + BUFSIZ + (buf?0:size), 1);
+ f = calloc(sizeof *f + sizeof *c + UNGET + BUFSIZ + (buf?0:size), 1);
if (!f) return 0;
+ f->cookie = c = (void *)(f+1);
f->fd = -1;
f->lbf = EOF;
- f->buf = (unsigned char *)(f+1) + UNGET;
+ f->buf = (unsigned char *)(c+1) + UNGET;
f->buf_size = BUFSIZ;
if (!buf) buf = f->buf + BUFSIZ;
+
+ c->buf = buf;
+ c->size = size;
+ c->mode = *mode;
if (!plus) f->flags = (*mode == 'r') ? F_NOWR : F_NORD;
- if (*mode == 'a') f->mempos = strchr(buf, 0)-buf;
+ if (*mode == 'r') c->len = size;
+ else if (*mode == 'a') c->len = c->pos = strnlen(buf, size);
f->read = mread;
f->write = mwrite;
f->seek = mseek;
- f->flush = mflush;
f->close = mclose;
+ if (!libc.threaded) {
+ f->lock = -1;
+ f->next = libc.ofl_head;
+ if (libc.ofl_head) libc.ofl_head->prev = f;
+ libc.ofl_head = f;
+ }
+
return f;
}
-#endif