consistently return number of bytes read from stdio read backend

the stdio FILE read backend's return type is size_t, not ssize_t, and
all of the special (non-fd-backed) FILE types already return the
number of bytes read (zero) on error or eof. only __stdio_read leaked
a syscall error return into its return value.

fread had a workaround for this behavior going all the way back to the
original check-in. remove the workaround since it's no longer needed.

diff --git a/src/stdio/__stdio_read.c b/src/stdio/__stdio_read.c
index af50508c2e8a71df12f4428e4ec4f2bf65cae0b3..909c36a9b9692b8a4ddcb2f9db6f28c9d9233c7b 100644 (file)
--- a/src/stdio/__stdio_read.c
+++ b/src/stdio/__stdio_read.c
@@ -12,7 +12,7 @@ size_t __stdio_read(FILE *f, unsigned char *buf, size_t len)
        cnt = syscall(SYS_readv, f->fd, iov, 2);
        if (cnt <= 0) {
                f->flags |= cnt ? F_ERR : F_EOF;
-               return cnt;
+               return 0;
        }
        if (cnt <= iov[0].iov_len) return cnt;
        cnt -= iov[0].iov_len;

diff --git a/src/stdio/fread.c b/src/stdio/fread.c
index aef75f7376f700dd584bf346ab1b7b17717ab097..733d37163aacf0ce20d2585dab0694c513db499a 100644 (file)
--- a/src/stdio/fread.c
+++ b/src/stdio/fread.c
@@ -25,7 +25,7 @@ size_t fread(void *restrict destv, size_t size, size_t nmemb, FILE *restrict f)
        /* Read the remainder directly */
        for (; l; l-=k, dest+=k) {
                k = __toread(f) ? 0 : f->read(f, dest, l);
-               if (k+1<=1) {
+               if (!k) {
                        FUNLOCK(f);
                        return (len-l)/size;
                }