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-rw-r--r--src/stdio/fmemopen.c51
1 files changed, 48 insertions, 3 deletions
diff --git a/src/stdio/fmemopen.c b/src/stdio/fmemopen.c
index 77a60746..cc72a420 100644
--- a/src/stdio/fmemopen.c
+++ b/src/stdio/fmemopen.c
@@ -3,14 +3,59 @@
static ssize_t mread(FILE *f, unsigned char *buf, size_t len)
{
- memcpy(buf,
+ size_t rem = f->memsize - f->mempos;
+ if (len > rem) len = rem;
+ memcpy(buf, f->membuf+f->mempos, len);
+ f->mempos += len;
+ return len;
+}
+
+static ssize_t mwrite(FILE *f, const unsigned char *buf, size_t len)
+{
+ 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;
+ }
+ return len;
}
FILE *fmemopen(void *buf, size_t size, const char *mode)
{
- FILE *f = calloc(sizeof(FILE), 1);
+ FILE *f;
+ int plus = !!strchr(mode, '+');
+
+ if (!size || !strchr("rwa", *mode)) {
+ errno = EINVAL;
+ return 0;
+ }
+
+ if (!buf && size > SIZE_MAX-sizeof(FILE)-BUFSIZ-UNGET) {
+ errno = ENOMEM;
+ return 0;
+ }
+
+ f = calloc(sizeof(FILE) + UNGET + BUFSIZ + (buf?0:size), 1);
if (!f) return 0;
+ f->fd = -1;
+ f->lbf = EOF;
+ f->buf = (unsigned char *)(f+1) + UNGET;
+ f->buf_size = BUFSIZ;
+ if (!buf) buf = f->buf + BUFSIZ;
- //
+ if (!plus) f->flags = (*mode == 'r') ? F_NOWR : F_NORD;
+ if (*mode == 'a') f->mempos = strchr(buf, 0)-buf;
+
+ f->read = mread;
+ f->write = mwrite;
+ f->seek = mseek;
+ f->flush = mflush;
+ f->close = mclose;
+
+ return f;
}
#endif