Changeset 6afc9d7 in mainline for uspace/lib/posix

Timestamp:

2015-10-06T19:01:36Z (10 years ago)

Author:

Jiri Svoboda <jiri@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

0328987

Parents:

f1f7584

Message:

UNIX-like I/O functions should use errno to return error code for many reasons.

Location:

uspace/lib/posix/source

Files:

• fcntl.c (modified) (1 diff)
• internal/common.h (modified) (2 diffs)
• stdio.c (modified) (4 diffs)
• stdlib.c (modified) (1 diff)
• sys/stat.c (modified) (2 diffs)
• unistd.c (modified) (12 diffs)

uspace/lib/posix/source/fcntl.c

@@ -112 +112 @@
         }
 
-        int rc = open(pathname, flags, mode);
-        if (rc < 0) {
-                errno = -rc;
-                rc = -1;
-        }
-
-        return rc;
+        return negerrno(open, pathname, flags, mode);
 }
 

uspace/lib/posix/source/internal/common.h

@@ -48 +48 @@
         } while (0)
 
-/* A little helper macro to avoid typing this over and over. */
+/* Convert negative error return value to positive errno */
 #define errnify(func, ...) ({ \
         int rc = func(__VA_ARGS__); \
@@ -58 +58 @@
 })
 
+/* Convert negative errno to positive errno */
+#define negerrno(func, ...) ({ \
+        int rc = func(__VA_ARGS__); \
+        if (rc < 0) { \
+                errno = -errno; \
+        } \
+        rc; \
+})
+
 #endif /* LIBPOSIX_COMMON_H_ */
 

uspace/lib/posix/source/stdio.c

@@ -315 +315 @@
 int posix_fflush(FILE *stream)
 {
-        int rc = fflush(stream);
-        if (rc < 0) {
-                errno = -rc;
-                return EOF;
-        } else {
-                return 0;
-        }
+        return negerrno(fflush, stream);
 }
 
@@ -351 +345 @@
 {
         ssize_t wr = write(*(int *) fd, str, size);
+        if (wr < 0)
+                return errno;
         return str_nlength(str, wr);
 }
@@ -579 +575 @@
 int posix_remove(const char *path)
 {
-        struct stat st;
-        int rc = stat(path, &st);
-        
-        if (rc != EOK) {
-                errno = -rc;
-                return -1;
-        }
-        
-        if (st.is_directory) {
-                rc = rmdir(path);
-        } else {
-                rc = unlink(path);
-        }
-        
-        if (rc != EOK) {
-                errno = -rc;
-                return -1;
-        }
-        return 0;
+        return negerrno(remove, path);
 }
 
@@ -609 +587 @@
 int posix_rename(const char *old, const char *new)
 {
-        return errnify(rename, old, new);
+        return negerrno(rename, old, new);
 }
 

uspace/lib/posix/source/stdlib.c

@@ -278 +278 @@
          * to be updated when that support is implemented.
          */
-        char* absolute = absolutize(name, NULL);
+        char* absolute = vfs_absolutize(name, NULL);
         
         if (absolute == NULL) {

uspace/lib/posix/source/sys/stat.c

@@ -80 +80 @@
 {
         struct stat hst;
-        int rc = fstat(fd, &hst);
-        if (rc < 0) {
-                /* fstat() returns negative error code instead of using errno. */
-                errno = -rc;
-                return -1;
-        }
+        int rc = negerrno(fstat, fd, &hst);
+        if (rc < 0)
+                return rc;
         stat_to_posix(st, &hst);
         return 0;
@@ -113 +110 @@
 {
         struct stat hst;
-        int rc = stat(path, &hst);
-        if (rc < 0) {
-                /* stat() returns negative error code instead of using errno. */
-                errno = -rc;
-                return -1;
-        }
+        int rc = negerrno(stat, path, &hst);
+        if (rc < 0)
+                return rc;
         stat_to_posix(st, &hst);
         return 0;

uspace/lib/posix/source/unistd.c

@@ -105 +105 @@
 char *posix_getcwd(char *buf, size_t size)
 {
-        /* Native getcwd() does not set any errno despite the fact that general
-         * usage pattern of this function depends on it (caller is repeatedly
-         * guessing the required size of the buffer by checking for ERANGE on
-         * failure). */
-        if (size == 0) {
-                errno = EINVAL;
+        char *p = getcwd(buf, size);
+
+        if (p == NULL) {
+                errno = -errno;
                 return NULL;
         }
-        
-        /* Save the original value to comply with the "no modification on
-         * success" semantics.
-         */
-        int orig_errno = errno;
-        errno = EOK;
-        
-        char *ret = getcwd(buf, size);
-        if (ret == NULL) {
-                /* Check errno to avoid shadowing other possible errors. */
-                if (errno == EOK) {
-                        errno = ERANGE;
-                }
-        } else {
-                /* Success, restore previous errno value. */
-                errno = orig_errno;
-        }
-        
-        return ret;
+
+        return p;
 }
 
@@ -141 +122 @@
 int posix_chdir(const char *path)
 {
-        return errnify(chdir, path);
+        return negerrno(chdir, path);
 }
 
@@ -194 +175 @@
 int posix_close(int fildes)
 {
-        return errnify(close, fildes);
+        return negerrno(close, fildes);
 }
 
@@ -207 +188 @@
 ssize_t posix_read(int fildes, void *buf, size_t nbyte)
 {
-        return errnify(read, fildes, buf, nbyte);
+        return negerrno(read, fildes, buf, nbyte);
 }
 
@@ -220 +201 @@
 ssize_t posix_write(int fildes, const void *buf, size_t nbyte)
 {
-        return errnify(write, fildes, buf, nbyte);
+        return negerrno(write, fildes, buf, nbyte);
 }
 
@@ -234 +215 @@
 posix_off_t posix_lseek(int fildes, posix_off_t offset, int whence)
 {
-        return errnify(lseek, fildes, offset, whence);
+        return negerrno(lseek, fildes, offset, whence);
 }
 
@@ -245 +226 @@
 int posix_fsync(int fildes)
 {
-        return errnify(fsync, fildes);
+        return negerrno(fsync, fildes);
 }
 
@@ -257 +238 @@
 int posix_ftruncate(int fildes, posix_off_t length)
 {
-        return errnify(ftruncate, fildes, (aoff64_t) length);
+        return negerrno(ftruncate, fildes, (aoff64_t) length);
 }
 
@@ -268 +249 @@
 int posix_rmdir(const char *path)
 {
-        return errnify(rmdir, path);
+        return negerrno(rmdir, path);
 }
 
@@ -279 +260 @@
 int posix_unlink(const char *path)
 {
-        return errnify(unlink, path);
+        return negerrno(unlink, path);
 }
 
@@ -303 +284 @@
 int posix_dup2(int fildes, int fildes2)
 {
-        return errnify(dup2, fildes, fildes2);
+        return negerrno(dup2, fildes, fildes2);
 }
 
@@ -321 +302 @@
                  * Check file existence by attempting to open it.
                  */
-                int fd = open(path, O_RDONLY);
+                int fd = negerrno(open, path, O_RDONLY);
                 if (fd < 0) {
-                        errno = -fd;
+                        /* errno was set by open() */
                         return -1;
                 }