correct locking in stdio functions that tried to be lock-free

[musl] / src / stdio / __fdopen.c

diff --git a/src/stdio/__fdopen.c b/src/stdio/__fdopen.c
index a010267..df6ed71 100644 (file)
--- a/src/stdio/__fdopen.c
+++ b/src/stdio/__fdopen.c
@@ -4,10 +4,12 @@ FILE *__fdopen(int fd, const char *mode)
 {
        FILE *f;
        struct termios tio;
-       int plus = !!strchr(mode, '+');
 
        /* Check for valid initial mode character */
-       if (!strchr("rwa", *mode)) return 0;
+       if (!strchr("rwa", *mode)) {
+               errno = EINVAL;
+               return 0;
+       }
 
        /* Allocate FILE+buffer or fail */
        if (!(f=malloc(sizeof *f + UNGET + BUFSIZ))) return 0;
@@ -16,12 +18,15 @@ FILE *__fdopen(int fd, const char *mode)
        memset(f, 0, sizeof *f);
 
        /* Impose mode restrictions */
-       if (!plus) f->flags = (*mode == 'r') ? F_NOWR : F_NORD;
+       if (!strchr(mode, '+')) f->flags = (*mode == 'r') ? F_NOWR : F_NORD;
+
+       /* Apply close-on-exec flag */
+       if (strchr(mode, 'e')) __syscall(SYS_fcntl, fd, F_SETFD, FD_CLOEXEC);
 
        /* Set append mode on fd if opened for append */
        if (*mode == 'a') {
-               int flags = syscall(SYS_fcntl, fd, F_GETFL, 0);
-               syscall(SYS_fcntl, fd, F_SETFL, flags | O_APPEND);
+               int flags = __syscall(SYS_fcntl, fd, F_GETFL);
+               __syscall(SYS_fcntl, fd, F_SETFL, flags | O_APPEND);
        }
 
        f->fd = fd;
@@ -39,11 +44,13 @@ FILE *__fdopen(int fd, const char *mode)
        f->seek = __stdio_seek;
        f->close = __stdio_close;
 
+       if (!libc.threaded) f->lock = -1;
+
        /* Add new FILE to open file list */
        OFLLOCK();
-       f->next = ofl_head;
-       if (ofl_head) ofl_head->prev = f;
-       ofl_head = f;
+       f->next = libc.ofl_head;
+       if (libc.ofl_head) libc.ofl_head->prev = f;
+       libc.ofl_head = f;
        OFLUNLOCK();
 
        return f;