Changes in uspace/lib/posix/source/unistd.c [6afc9d7:820104d] in mainline

File:

• uspace/lib/posix/source/unistd.c (modified) (12 diffs)

uspace/lib/posix/source/unistd.c

@@ -105 +105 @@
 char *posix_getcwd(char *buf, size_t size)
 {
-        char *p = getcwd(buf, size);
-
-        if (p == NULL) {
-                errno = -errno;
+        /* 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;
                 return NULL;
         }
-
-        return p;
+        
+        /* 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;
 }
 
@@ -122 +141 @@
 int posix_chdir(const char *path)
 {
-        return negerrno(chdir, path);
+        return errnify(chdir, path);
 }
 
@@ -175 +194 @@
 int posix_close(int fildes)
 {
-        return negerrno(close, fildes);
+        return errnify(close, fildes);
 }
 
@@ -188 +207 @@
 ssize_t posix_read(int fildes, void *buf, size_t nbyte)
 {
-        return negerrno(read, fildes, buf, nbyte);
+        return errnify(read, fildes, buf, nbyte);
 }
 
@@ -201 +220 @@
 ssize_t posix_write(int fildes, const void *buf, size_t nbyte)
 {
-        return negerrno(write, fildes, buf, nbyte);
+        return errnify(write, fildes, buf, nbyte);
 }
 
@@ -215 +234 @@
 posix_off_t posix_lseek(int fildes, posix_off_t offset, int whence)
 {
-        return negerrno(lseek, fildes, offset, whence);
+        return errnify(lseek, fildes, offset, whence);
 }
 
@@ -226 +245 @@
 int posix_fsync(int fildes)
 {
-        return negerrno(fsync, fildes);
+        return errnify(fsync, fildes);
 }
 
@@ -238 +257 @@
 int posix_ftruncate(int fildes, posix_off_t length)
 {
-        return negerrno(ftruncate, fildes, (aoff64_t) length);
+        return errnify(ftruncate, fildes, (aoff64_t) length);
 }
 
@@ -249 +268 @@
 int posix_rmdir(const char *path)
 {
-        return negerrno(rmdir, path);
+        return errnify(rmdir, path);
 }
 
@@ -260 +279 @@
 int posix_unlink(const char *path)
 {
-        return negerrno(unlink, path);
+        return errnify(unlink, path);
 }
 
@@ -284 +303 @@
 int posix_dup2(int fildes, int fildes2)
 {
-        return negerrno(dup2, fildes, fildes2);
+        return errnify(dup2, fildes, fildes2);
 }
 
@@ -302 +321 @@
                  * Check file existence by attempting to open it.
                  */
-                int fd = negerrno(open, path, O_RDONLY);
+                int fd = open(path, O_RDONLY);
                 if (fd < 0) {
-                        /* errno was set by open() */
+                        errno = -fd;
                         return -1;
                 }