From: Simon Ruderich <simon@ruderich.org>
Date: Sat, 1 Jun 2013 20:47:23 +0000 (+0200)
Subject: hookmacros.h: Be more careful to restore the errno.
X-Git-Tag: 0.1~125
X-Git-Url: https://ruderich.org/simon/gitweb/?p=coloredstderr%2Fcoloredstderr.git;a=commitdiff_plain;h=66140e14e485af27f5234ae7b744a50dff3dd4c9

hookmacros.h: Be more careful to restore the errno.

check_handle_fd() or handle_fd_pre() might also modify it.
---

diff --git a/src/hookmacros.h b/src/hookmacros.h
index 09e718a..6f65d1e 100644
--- a/src/hookmacros.h
+++ b/src/hookmacros.h
@@ -26,6 +26,7 @@
 
 #define _HOOK_PRE(type, name) \
         int handle; \
+        int saved_errno = errno; \
         DLSYM_FUNCTION(real_ ## name, #name);
 #define _HOOK_PRE_FD(type, name, fd) \
         type result; \
@@ -35,19 +36,21 @@
         handle = check_handle_fd(fd); \
         if (handle) { \
             handle_fd_pre(fd, handle); \
-        }
+        } \
+        errno = saved_errno;
 #define _HOOK_PRE_FILE(type, name, file) \
         type result; \
         _HOOK_PRE(type, name) \
         handle = check_handle_fd(fileno(file)); \
         if (handle) { \
             handle_file_pre(file, handle); \
-        }
+        } \
+        errno = saved_errno;
 /* Save and restore the errno to make sure we return the errno of the original
  * function call. */
 #define _HOOK_POST_FD_(fd) \
         if (handle) { \
-            int saved_errno = errno; \
+            saved_errno = errno; \
             handle_fd_post(fd, handle); \
             errno = saved_errno; \
         }
@@ -56,7 +59,7 @@
         return result;
 #define _HOOK_POST_FILE(file) \
         if (handle) { \
-            int saved_errno = errno; \
+            saved_errno = errno; \
             handle_file_post(file, handle); \
             errno = saved_errno; \
         } \