fix some fmemopen behaviors

[musl] / src / stdio / fmemopen.c

diff --git a/src/stdio/fmemopen.c b/src/stdio/fmemopen.c
index e2adfb2..260d288 100644 (file)
--- a/src/stdio/fmemopen.c
+++ b/src/stdio/fmemopen.c
@@ -23,7 +23,8 @@ fail:
 static size_t mread(FILE *f, unsigned char *buf, size_t len)
 {
        struct cookie *c = f->cookie;
 static size_t mread(FILE *f, unsigned char *buf, size_t len)
 {
        struct cookie *c = f->cookie;

-       size_t rem = c->size - c->pos;
+       size_t rem = c->len - c->pos;
+       if (c->pos > c->len) rem = 0;

        if (len > rem) {
                len = rem;
                f->flags |= F_EOF;
        if (len > rem) {
                len = rem;
                f->flags |= F_EOF;


@@ -48,13 +49,15 @@ static size_t mwrite(FILE *f, const unsigned char *buf, size_t len)
                f->wpos = f->wbase;
                if (mwrite(f, f->wpos, len2) < len2) return 0;
        }
                f->wpos = f->wbase;
                if (mwrite(f, f->wpos, len2) < len2) return 0;
        }

-       if (c->mode == 'a') c->pos = c->size;
+       if (c->mode == 'a') c->pos = c->len;

        rem = c->size - c->pos;
        if (len > rem) len = rem;
        memcpy(c->buf+c->pos, buf, len);
        c->pos += len;
        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;
+       if (c->pos >= c->len) {
+               c->len = c->pos;
+               c->buf[c->len==c->size ? c->len-1 : c->len] = 0;
+       }

        return len;
 }
 
        return len;
 }