From 3d46e3ab9b45d83f69e79a338a45f316e3f61dc0 Mon Sep 17 00:00:00 2001
From: Simon Ruderich <simon@ruderich.org>
Date: Thu, 13 Jun 2013 22:13:16 +0200
Subject: [PATCH 01/16] Add missing const and document where it can't be used.

---
 src/coloredstderr.c | 4 ++--
 src/debug.h         | 2 +-
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/src/coloredstderr.c b/src/coloredstderr.c
index 0d76b5a..3fe2053 100644
--- a/src/coloredstderr.c
+++ b/src/coloredstderr.c
@@ -507,14 +507,14 @@ int execve(char const *filename, char * const argv[], char * const env[]) {
     /* Count arguments. */ \
     size_t count = 1; /* arg */ \
     va_start(ap, arg); \
-    while (va_arg(ap, char const *)) { \
+    while (va_arg(ap, char *)) { \
         count++; \
     } \
     va_end(ap); \
     \
     /* Copy varargs. */ \
     char *args[count + 1 /* terminating NULL */]; \
-    args[0] = (char *)arg; \
+    args[0] = (char *)arg; /* there's no other way around the cast */ \
     \
     size_t i = 1; \
     va_start(ap, arg); \
diff --git a/src/debug.h b/src/debug.h
index 5e5cc6d..911a440 100644
--- a/src/debug.h
+++ b/src/debug.h
@@ -36,7 +36,7 @@ static void debug_write(int fd, int first_call, char const *format, va_list ap)
     DLSYM_FUNCTION(real_close, "close");
 
     if (first_call) {
-        char nl = '\n';
+        char const nl = '\n';
         real_write(fd, &nl, 1);
     }
     real_write(fd, buffer, (size_t)written);
-- 
2.44.1


From 45d25526c0df734a5eeb926b0e733e19bfbdb8c2 Mon Sep 17 00:00:00 2001
From: Simon Ruderich <simon@ruderich.org>
Date: Thu, 13 Jun 2013 22:15:09 +0200
Subject: [PATCH 02/16] Minor documentation updates.

---
 src/trackfds.h | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/src/trackfds.h b/src/trackfds.h
index 70751d7..56490ad 100644
--- a/src/trackfds.h
+++ b/src/trackfds.h
@@ -100,7 +100,7 @@ static void init_from_environment(void) {
 #ifdef DEBUG
     debug("  getenv(\"%s\"): \"%s\"\n", ENV_NAME_FDS, env);
 #endif
-    /* Environment is read-only. */
+    /* Environment must be treated read-only. */
     char env_copy[strlen(env) + 1];
     strcpy(env_copy, env);
 
@@ -132,6 +132,7 @@ static void init_from_environment(void) {
             break;
         }
 
+        /* Replace ',' to null-terminate number for atoi(). */
         *x = 0;
 
         int fd = atoi(last);
@@ -184,7 +185,7 @@ static char *update_environment_buffer_entry(char *x, int fd) {
     /* Write comma after number. */
     x += length;
     *x++ = ',';
-    /* Make sure the string is always zero terminated. */
+    /* Make sure the string is always null-terminated. */
     *x = 0;
 
     return x;
-- 
2.44.1


From 1d1b6d77696e233235d558af9d66bc6edb184ca0 Mon Sep 17 00:00:00 2001
From: Simon Ruderich <simon@ruderich.org>
Date: Thu, 13 Jun 2013 22:15:49 +0200
Subject: [PATCH 03/16] Remove duplicate code in init_from_environment().

---
 src/trackfds.h | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/src/trackfds.h b/src/trackfds.h
index 56490ad..acf7ce3 100644
--- a/src/trackfds.h
+++ b/src/trackfds.h
@@ -124,8 +124,7 @@ static void init_from_environment(void) {
         }
         /* ',' at the beginning or double ',' - ignore. */
         if (x == last) {
-            last = x + 1;
-            continue;
+            goto next;
         }
 
         if (i == count) {
-- 
2.44.1


From d5b84811d2f4bded83211984c839a096872608af Mon Sep 17 00:00:00 2001
From: Simon Ruderich <simon@ruderich.org>
Date: Thu, 13 Jun 2013 22:35:42 +0200
Subject: [PATCH 04/16] tests/lib.sh: Fix tests for dash.

---
 tests/lib.sh | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/tests/lib.sh b/tests/lib.sh
index 897d50e..3427b56 100644
--- a/tests/lib.sh
+++ b/tests/lib.sh
@@ -105,7 +105,9 @@ run_test() {
 test_script() {
     testcase="$1"
     expected="$2"
-    shift; shift || true
+    # shift || true is not enough for dash.
+    test $# -ge 2 && shift
+    shift
 
     if test -z "$expected"; then
         expected="$testcase"
@@ -118,7 +120,8 @@ test_script_subshell() {
 test_program() {
     testcase="$1"
     expected="$2"
-    shift; shift || true
+    test $# -ge 2 && shift
+    shift
 
     if test -z "$expected"; then
         expected="$testcase"
-- 
2.44.1


From 208757de8875b3719331024d246e9a7324094993 Mon Sep 17 00:00:00 2001
From: Simon Ruderich <simon@ruderich.org>
Date: Thu, 13 Jun 2013 22:43:43 +0200
Subject: [PATCH 05/16] .gitignore: Ignore generated test files.

Forgotten in d8be625da928025e96417c1b62f3336251204cef and
59375c2b7949791d8cad8e5cebde2649bac83ec8.
---
 .gitignore | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/.gitignore b/.gitignore
index 6401ebd..989a240 100644
--- a/.gitignore
+++ b/.gitignore
@@ -29,6 +29,8 @@
 /tests/example_exec.o
 /tests/example_vfork
 /tests/example_vfork.o
+/tests/test_environment.sh.log
+/tests/test_environment.sh.trs
 /tests/test_error.sh.log
 /tests/test_error.sh.trs
 /tests/test_example.sh.log
@@ -41,6 +43,8 @@
 /tests/test_redirects.sh.trs
 /tests/test_simple.sh.log
 /tests/test_simple.sh.trs
+/tests/test_symbols.sh.log
+/tests/test_symbols.sh.trs
 /tests/test_vfork.sh.log
 /tests/test_vfork.sh.trs
 /tests/test-suite.log
-- 
2.44.1


From 04334418fcce94a1b528bd4c935d8126876bda04 Mon Sep 17 00:00:00 2001
From: Simon Ruderich <simon@ruderich.org>
Date: Fri, 14 Jun 2013 11:07:40 +0200
Subject: [PATCH 06/16] README: Add first part of installation instructions.

---
 README | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

diff --git a/README b/README
index 6bedd74..5e9917a 100644
--- a/README
+++ b/README
@@ -31,6 +31,27 @@ DEPENDENCIES
 - dynamic linker/loader which supports 'LD_PRELOAD' (e.g. GNU/Linux's ld.so)
 
 
+INSTALLATION
+------------
+
+    ./configure && make && make check
+
+Then either install the library with `make install` or just copy it from
+`src/.libs/` to wherever you want to install it:
+
+    rm -f /destination/path/for/library/libcoloredstderr.so
+    cp -L src/.libs/libcoloredstderr.so /destination/path/for/library/
+
+*Important:* If you install `libcoloredstderr.so` manually, make sure _not_ to
+use plain `cp` to overwrite an existing `libcoloredstderr.so` file which is in
+use! Doing so will crash all processes which were started with 'LD_PRELOAD'
+set to this file. This is not a bug in coloredstderr, but a general problem.
+`cp` truncates the file which causes the `mmap()` ed library to be in an
+inconsistent state causing a segmentation fault when using any functions of
+the library. Just remove the file first and then copy it. `make install`
+handles the install in this way and is therefore not affected.
+
+
 USAGE
 -----
 
-- 
2.44.1


From dcaadb5f7c530d348d936bf642ada9ef1ea855d1 Mon Sep 17 00:00:00 2001
From: Simon Ruderich <simon@ruderich.org>
Date: Fri, 14 Jun 2013 12:44:34 +0200
Subject: [PATCH 07/16] README: Explain how to modify pre/post variables.

---
 README | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/README b/README
index 5e9917a..34cff30 100644
--- a/README
+++ b/README
@@ -89,6 +89,21 @@ The following additional environment variables are available:
   are colored.
 
 
+To set custom colors as pre/post strings you can use the `$''` feature of Bash
+and Zsh:
+
+    export COLORED_STDERR_PRE=$'\033[91m' # bright red
+    export COLORED_STDERR_POST=$'\033[0m' # default
+
+Or to be more compatible you can use the following which should work in any
+Bourne shell:
+
+    esc=`printf '\033'`
+    COLORED_STDERR_PRE="${esc}[91m" # red
+    COLORED_STDERR_POST="${esc}[0m" # default
+    export COLORED_STDERR_PRE COLORED_STDERR_POST
+
+
 DEBUG
 -----
 
-- 
2.44.1


From 18d52b3b5a11b9625a4780bff85ed9dc49af93fc Mon Sep 17 00:00:00 2001
From: Simon Ruderich <simon@ruderich.org>
Date: Fri, 14 Jun 2013 13:40:06 +0200
Subject: [PATCH 08/16] Install libcoloredstderr.so read-only.

Prevents accidental truncates of libcoloredstderr.so with `cp` which
crash all programs which have loaded it.
---
 README          | 5 +++++
 src/Makefile.am | 9 +++++++++
 2 files changed, 14 insertions(+)

diff --git a/README b/README
index 34cff30..298ce4f 100644
--- a/README
+++ b/README
@@ -51,6 +51,11 @@ inconsistent state causing a segmentation fault when using any functions of
 the library. Just remove the file first and then copy it. `make install`
 handles the install in this way and is therefore not affected.
 
+As a simple safeguard, `make` builds and installs the `libcoloredstderr.so`
+file non-writable to prevent accidental overwrites. Even if the overwrite is
+forced with `cp -f`, the file is unlinked and recreated by `cp` because the
+file is non-writable, preventing the problem.
+
 
 USAGE
 -----
diff --git a/src/Makefile.am b/src/Makefile.am
index 1526e1d..46f9289 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -6,3 +6,12 @@ libcoloredstderr_la_SOURCES = coloredstderr.c \
                               hookmacros.h \
                               ldpreload.h \
                               trackfds.h
+
+# Make sure the library is not writable. See README why this is important. Is
+# not run with `make libcoloredstderr.la`, but this isn't common usage.
+all-local: $(lib_LTLIBRARIES)
+	find .libs -type f -exec chmod ugo-w '{}' \;
+# `install` uses normal permissions, "fix" them so `make install` also
+# installs non-writable files.
+install-exec-hook:
+	find $(DESTDIR)$(libdir) -type f -exec chmod ugo-w '{}' \;
-- 
2.44.1


From 6ae629bef0e8bd48bc6bb311a9ea12ee462091a2 Mon Sep 17 00:00:00 2001
From: Simon Ruderich <simon@ruderich.org>
Date: Fri, 14 Jun 2013 15:27:31 +0200
Subject: [PATCH 09/16] tests/Makefile.am: Enable parallel and colored test
 runs.

Necessary for automake < 1.13.
---
 tests/Makefile.am | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/tests/Makefile.am b/tests/Makefile.am
index 2a3749f..80d0cdd 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -1,3 +1,6 @@
+# Default since automake 1.13, necessary for older versions.
+AUTOMAKE_OPTIONS = color-tests parallel-tests
+
 TESTS = test_environment.sh \
         test_example.sh \
         test_exec.sh \
-- 
2.44.1


From 9507e0f60ddf054034e1673bd21709aedadee48e Mon Sep 17 00:00:00 2001
From: Simon Ruderich <simon@ruderich.org>
Date: Fri, 14 Jun 2013 15:33:28 +0200
Subject: [PATCH 10/16] configure.ac: Fix Vim's syntax coloring issue with
 `..'.

---
 configure.ac | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/configure.ac b/configure.ac
index 09d90a0..a939d8a 100644
--- a/configure.ac
+++ b/configure.ac
@@ -50,7 +50,7 @@ AX_C___ATTRIBUTE__
 AC_CHECK_MEMBER([struct _IO_FILE._fileno],
                 [AC_DEFINE([HAVE_STRUCT__IO_FILE__FILENO], 1,
                            [Define to 1 if `_fileno' is a member of `struct _IO_FILE'.])],
-                [],[[#include <libio.h>]])
+                [],[[#include <libio.h>]]) dnl ' fix for vim syntax coloring
 
 AC_FUNC_FORK
 AC_CHECK_FUNCS([memmove setenv],
-- 
2.44.1


From 217e8c8bc5fa8c22221514a320d6edeb1c2a101f Mon Sep 17 00:00:00 2001
From: Simon Ruderich <simon@ruderich.org>
Date: Sat, 15 Jun 2013 00:54:46 +0200
Subject: [PATCH 11/16] Define real_*() static variables with macros.

---
 src/coloredstderr.c | 36 ++++++++++++++++++------------------
 src/hookmacros.h    | 14 ++++++++++++++
 2 files changed, 32 insertions(+), 18 deletions(-)

diff --git a/src/coloredstderr.c b/src/coloredstderr.c
index 3fe2053..34d3293 100644
--- a/src/coloredstderr.c
+++ b/src/coloredstderr.c
@@ -336,10 +336,8 @@ void error(int status, int errnum, char const *format, ...) {
 
 /* Hook functions which duplicate file descriptors to track them. */
 
-static int (*real_dup)(int);
-static int (*real_dup2)(int, int);
-static int (*real_dup3)(int, int, int);
-int dup(int oldfd) {
+/* int dup(int) */
+HOOK_FUNC_DEF1(int, dup, int, oldfd) {
     int newfd;
 
     DLSYM_FUNCTION(real_dup, "dup");
@@ -351,7 +349,8 @@ int dup(int oldfd) {
 
     return newfd;
 }
-int dup2(int oldfd, int newfd) {
+/* int dup2(int, int) */
+HOOK_FUNC_DEF2(int, dup2, int, oldfd, int, newfd) {
     DLSYM_FUNCTION(real_dup2, "dup2");
 
     newfd = real_dup2(oldfd, newfd);
@@ -361,7 +360,8 @@ int dup2(int oldfd, int newfd) {
 
     return newfd;
 }
-int dup3(int oldfd, int newfd, int flags) {
+/* int dup3(int, int, int) */
+HOOK_FUNC_DEF3(int, dup3, int, oldfd, int, newfd, int, flags) {
     DLSYM_FUNCTION(real_dup3, "dup3");
 
     newfd = real_dup3(oldfd, newfd, flags);
@@ -372,8 +372,8 @@ int dup3(int oldfd, int newfd, int flags) {
     return newfd;
 }
 
-static int (*real_fcntl)(int, int, ...);
-int fcntl(int fd, int cmd, ...) {
+/* int fcntl(int, int, ...) */
+HOOK_FUNC_VAR_DEF2(int, fcntl, int, fd, int, cmd /*, ... */) {
     int result;
     va_list ap;
 
@@ -404,8 +404,8 @@ int fcntl(int fd, int cmd, ...) {
     return result;
 }
 
-static int (*real_close)(int);
-int close(int fd) {
+/* int close(int) */
+HOOK_FUNC_DEF1(int, close, int, fd) {
     DLSYM_FUNCTION(real_close, "close");
 
     if (fd >= 0) {
@@ -413,8 +413,8 @@ int close(int fd) {
     }
     return real_close(fd);
 }
-static int (*real_fclose)(FILE *);
-int fclose(FILE *fp) {
+/* int fclose(FILE *) */
+HOOK_FUNC_DEF1(int, fclose, FILE *, fp) {
     int fd;
 
     DLSYM_FUNCTION(real_fclose, "fclose");
@@ -451,8 +451,8 @@ pid_t vfork(void) {
  * ENV_NAME_FDS. It's also faster to update the environment only when
  * necessary, right before the exec() to pass it to the new process. */
 
-static int (*real_execve)(char const *filename, char * const argv[], char * const env[]);
-int execve(char const *filename, char * const argv[], char * const env[]) {
+/* int execve(char const *, char * const [], char * const []) */
+HOOK_FUNC_DEF3(int, execve, char const *, filename, char * const *, argv, char * const *, env) {
     DLSYM_FUNCTION(real_execve, "execve");
 
     int found = 0;
@@ -552,16 +552,16 @@ int execle(char const *path, char const *arg, ... /*, char * const envp[] */) {
     return execve(path, args, envp);
 }
 
-static int (*real_execv)(char const *path, char * const argv[]);
-int execv(char const *path, char * const argv[]) {
+/* int execv(char const *, char * const []) */
+HOOK_FUNC_DEF2(int, execv, char const *, path, char * const *, argv) {
     DLSYM_FUNCTION(real_execv, "execv");
 
     update_environment();
     return real_execv(path, argv);
 }
 
-static int (*real_execvp)(char const *path, char * const argv[]);
-int execvp(char const *file, char * const argv[]) {
+/* int execvp(char const *, char * const []) */
+HOOK_FUNC_DEF2(int, execvp, char const *, file, char * const *, argv) {
     DLSYM_FUNCTION(real_execvp, "execvp");
 
     update_environment();
diff --git a/src/hookmacros.h b/src/hookmacros.h
index 42273e4..ebd5f7a 100644
--- a/src/hookmacros.h
+++ b/src/hookmacros.h
@@ -101,6 +101,20 @@
         return result;
 
 
+#define HOOK_FUNC_DEF1(type, name, type1, arg1) \
+    static type (*real_ ## name)(type1); \
+    type name(type1 arg1)
+#define HOOK_FUNC_DEF2(type, name, type1, arg1, type2, arg2) \
+    static type (*real_ ## name)(type1, type2); \
+    type name(type1 arg1, type2 arg2)
+#define HOOK_FUNC_DEF3(type, name, type1, arg1, type2, arg2, type3, arg3) \
+    static type (*real_ ## name)(type1, type2, type3); \
+    type name(type1 arg1, type2 arg2, type3 arg3)
+
+#define HOOK_FUNC_VAR_DEF2(type, name, type1, arg1, type2, arg2) \
+    static type (*real_ ## name)(type1, type2, ...); \
+    type name(type1 arg1, type2 arg2, ...)
+
 #define HOOK_VOID1(type, name, fd, type1, arg1) \
     static type (*real_ ## name)(type1); \
     type name(type1 arg1) { \
-- 
2.44.1


From 0a909cac79e9d46ad6470b9deab9df9493f66a69 Mon Sep 17 00:00:00 2001
From: Simon Ruderich <simon@ruderich.org>
Date: Sat, 15 Jun 2013 01:58:36 +0200
Subject: [PATCH 12/16] Use locally defined functions in hooks where possible.

Don't create a hook and call the "real" function when it's enough to
call an existing hook for this function.
---
 src/hookmacros.h | 18 ++++++------------
 1 file changed, 6 insertions(+), 12 deletions(-)

diff --git a/src/hookmacros.h b/src/hookmacros.h
index ebd5f7a..9ee05db 100644
--- a/src/hookmacros.h
+++ b/src/hookmacros.h
@@ -168,34 +168,28 @@
     }
 
 #define HOOK_VAR_FILE1(type, name, file, func, type1, arg1) \
-    static type (*real_ ## func)(type1, va_list); \
     type name(type1 arg1, ...) { \
         va_list ap; \
-        _HOOK_PRE_FILE(type, func, file) \
         va_start(ap, arg1); \
-        result = real_ ## func(arg1, ap); \
+        type result = func(arg1, ap); \
         va_end(ap); \
-        _HOOK_POST_FILE(file) \
+        return result; \
     }
 #define HOOK_VAR_FILE2(type, name, file, func, type1, arg1, type2, arg2) \
-    static type (*real_ ## func)(type1, type2, va_list); \
     type name(type1 arg1, type2 arg2, ...) { \
         va_list ap; \
-        _HOOK_PRE_FILE(type, func, file) \
         va_start(ap, arg2); \
-        result = real_ ## func(arg1, arg2, ap); \
+        type result = func(arg1, arg2, ap); \
         va_end(ap); \
-        _HOOK_POST_FILE(file) \
+        return result; \
     }
 #define HOOK_VAR_FILE3(type, name, file, func, type1, arg1, type2, arg2, type3, arg3) \
-    static type (*real_ ## func)(type1, type2, type3, va_list); \
     type name(type1 arg1, type2 arg2, type3 arg3, ...) { \
         va_list ap; \
-        _HOOK_PRE_FILE(type, func, file) \
         va_start(ap, arg3); \
-        result = real_ ## func(arg1, arg2, arg3, ap); \
+        type result = func(arg1, arg2, arg3, ap); \
         va_end(ap); \
-        _HOOK_POST_FILE(file) \
+        return result; \
     }
 
 #endif
-- 
2.44.1


From 1068648718dad86471451266fcdf4248bb79f3fe Mon Sep 17 00:00:00 2001
From: Simon Ruderich <simon@ruderich.org>
Date: Sat, 15 Jun 2013 02:21:27 +0200
Subject: [PATCH 13/16] Minor documentation update.

---
 configure.ac        | 2 +-
 src/coloredstderr.c | 2 +-
 src/compiler.h      | 3 ++-
 3 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/configure.ac b/configure.ac
index a939d8a..0a8f2a8 100644
--- a/configure.ac
+++ b/configure.ac
@@ -80,7 +80,7 @@ AC_ARG_ENABLE([debug],
                    AC_DEFINE([WARNING], 1)
                fi])
 
-dnl Used in tests/Makefile.am to build the test only if error() is available.
+dnl Used in tests/Makefile.am to build the test only if function is available.
 AM_CONDITIONAL([HAVE_ERROR_H],[test "x$ac_cv_header_error_h" = xyes])
 AM_CONDITIONAL([HAVE_VFORK],[test "x$ac_cv_func_vfork_works" = xyes])
 
diff --git a/src/coloredstderr.c b/src/coloredstderr.c
index 34d3293..eb9d92c 100644
--- a/src/coloredstderr.c
+++ b/src/coloredstderr.c
@@ -265,7 +265,7 @@ HOOK_FD2(int, __overflow, f->_fileno, _IO_FILE *, f, int, ch)
 HOOK_VOID1(void, perror, STDERR_FILENO,
            char const *, s)
 
-/* error(3) */
+/* error(3), non-standard GNU extension */
 #ifdef HAVE_ERROR_H
 static void error_vararg(int status, int errnum,
                          char const *filename, unsigned int linenum,
diff --git a/src/compiler.h b/src/compiler.h
index 5ede8b2..85b58b1 100644
--- a/src/compiler.h
+++ b/src/compiler.h
@@ -20,10 +20,11 @@
 #ifndef COMPILER_H
 #define COMPILER_H 1
 
-/* Prevent/force inlining. Used to improve performance. */
 #ifdef HAVE___ATTRIBUTE__
+/* Prevent/force inlining. Used to improve performance. */
 # define noinline      __attribute__((noinline))
 # define always_inline __attribute__((always_inline))
+/* Unused parameter. */
 # define unused        __attribute__((unused))
 #else
 # define noinline
-- 
2.44.1


From 941370dda9f22ca42e1d5b3cd580d7e7091d40bc Mon Sep 17 00:00:00 2001
From: Simon Ruderich <simon@ruderich.org>
Date: Sat, 15 Jun 2013 02:39:52 +0200
Subject: [PATCH 14/16] Hook BSD err(), errx(), warn(), warnx(), etc.
 functions.

err(), errx(), warn(), warnx(), verr(), verrx(), vwarn(), vwarnx() are
hooked.
---
 .gitignore                 |  4 +++
 configure.ac               |  3 ++-
 src/coloredstderr.c        | 30 ++++++++++++++++++++++
 src/hookmacros.h           | 32 ++++++++++++++++++++++++
 tests/Makefile.am          |  9 ++++++-
 tests/example.h            | 38 ++++++++++++++++++++++++++++
 tests/example_err.c        | 51 ++++++++++++++++++++++++++++++++++++++
 tests/example_err.expected | 11 ++++++++
 tests/test_err.sh          | 23 +++++++++++++++++
 9 files changed, 199 insertions(+), 2 deletions(-)
 create mode 100644 tests/example.h
 create mode 100644 tests/example_err.c
 create mode 100644 tests/example_err.expected
 create mode 100755 tests/test_err.sh

diff --git a/.gitignore b/.gitignore
index 989a240..a279991 100644
--- a/.gitignore
+++ b/.gitignore
@@ -23,6 +23,8 @@
 /tests/Makefile.in
 /tests/example
 /tests/example.o
+/tests/example_err
+/tests/example_err.o
 /tests/example_error
 /tests/example_error.o
 /tests/example_exec
@@ -31,6 +33,8 @@
 /tests/example_vfork.o
 /tests/test_environment.sh.log
 /tests/test_environment.sh.trs
+/tests/test_err.sh.log
+/tests/test_err.sh.trs
 /tests/test_error.sh.log
 /tests/test_error.sh.trs
 /tests/test_example.sh.log
diff --git a/configure.ac b/configure.ac
index 0a8f2a8..a96edb4 100644
--- a/configure.ac
+++ b/configure.ac
@@ -36,7 +36,7 @@ if test "x$GCC" = xyes; then
     CFLAGS="-Wall -Wextra -Wconversion $CFLAGS"
 fi
 
-AC_CHECK_HEADERS([error.h])
+AC_CHECK_HEADERS([err.h error.h])
 AC_CHECK_HEADERS([fcntl.h],
                  [],[AC_MSG_ERROR([header is required])])
 
@@ -81,6 +81,7 @@ AC_ARG_ENABLE([debug],
                fi])
 
 dnl Used in tests/Makefile.am to build the test only if function is available.
+AM_CONDITIONAL([HAVE_ERR_H],[test "x$ac_cv_header_err_h" = xyes])
 AM_CONDITIONAL([HAVE_ERROR_H],[test "x$ac_cv_header_error_h" = xyes])
 AM_CONDITIONAL([HAVE_VFORK],[test "x$ac_cv_func_vfork_works" = xyes])
 
diff --git a/src/coloredstderr.c b/src/coloredstderr.c
index eb9d92c..247bd06 100644
--- a/src/coloredstderr.c
+++ b/src/coloredstderr.c
@@ -38,6 +38,9 @@
 #include <string.h>
 #include <unistd.h>
 
+#ifdef HAVE_ERR_H
+# include <err.h>
+#endif
 #ifdef HAVE_ERROR_H
 # include <error.h>
 #endif
@@ -265,6 +268,33 @@ HOOK_FD2(int, __overflow, f->_fileno, _IO_FILE *, f, int, ch)
 HOOK_VOID1(void, perror, STDERR_FILENO,
            char const *, s)
 
+/* err(3), non standard BSD extension */
+#ifdef HAVE_ERR_H
+HOOK_VAR_VOID2(void, err, STDERR_FILENO, verr,
+               int, eval, char const *, fmt)
+HOOK_VAR_VOID2(void, errx, STDERR_FILENO, verrx,
+               int, eval, char const *, fmt)
+HOOK_VAR_VOID1(void, warn, STDERR_FILENO, vwarn,
+               char const *, fmt)
+HOOK_VAR_VOID1(void, warnx, STDERR_FILENO, vwarnx,
+               char const *, fmt)
+HOOK_FUNC_SIMPLE3(void, verr, int, eval, const char *, fmt, va_list, args) {
+    /* Can't use verr() directly as it terminates the process which prevents
+     * the post string from being printed. */
+    vwarn(fmt, args);
+    exit(eval);
+}
+HOOK_FUNC_SIMPLE3(void, verrx, int, eval, const char *, fmt, va_list, args) {
+    /* See verr(). */
+    vwarnx(fmt, args);
+    exit(eval);
+}
+HOOK_VOID2(void, vwarn, STDERR_FILENO,
+           char const *, fmt, va_list, args)
+HOOK_VOID2(void, vwarnx, STDERR_FILENO,
+           char const *, fmt, va_list, args)
+#endif
+
 /* error(3), non-standard GNU extension */
 #ifdef HAVE_ERROR_H
 static void error_vararg(int status, int errnum,
diff --git a/src/hookmacros.h b/src/hookmacros.h
index 9ee05db..18a828e 100644
--- a/src/hookmacros.h
+++ b/src/hookmacros.h
@@ -115,6 +115,9 @@
     static type (*real_ ## name)(type1, type2, ...); \
     type name(type1 arg1, type2 arg2, ...)
 
+#define HOOK_FUNC_SIMPLE3(type, name, type1, arg1, type2, arg2, type3, arg3) \
+    type name(type1 arg1, type2 arg2, type3 arg3)
+
 #define HOOK_VOID1(type, name, fd, type1, arg1) \
     static type (*real_ ## name)(type1); \
     type name(type1 arg1) { \
@@ -122,6 +125,35 @@
         real_ ## name(arg1); \
         _HOOK_POST_FD_(fd) \
     }
+#define HOOK_VOID2(type, name, fd, type1, arg1, type2, arg2) \
+    static type (*real_ ## name)(type1, type2); \
+    type name(type1 arg1, type2 arg2) { \
+        _HOOK_PRE_FD_(type, name, fd) \
+        real_ ## name(arg1, arg2); \
+        _HOOK_POST_FD_(fd) \
+    }
+#define HOOK_VOID3(type, name, fd, type1, arg1, type2, arg2, type3, arg3) \
+    static type (*real_ ## name)(type1, type2, type3); \
+    type name(type1 arg1, type2 arg2, type3 arg3) { \
+        _HOOK_PRE_FD_(type, name, fd) \
+        real_ ## name(arg1, arg2, arg3); \
+        _HOOK_POST_FD_(fd) \
+    }
+
+#define HOOK_VAR_VOID1(type, name, fd, func, type1, arg1) \
+    type name(type1 arg1, ...) { \
+        va_list ap; \
+        va_start(ap, arg1); \
+        func(arg1, ap); \
+        va_end(ap); \
+    }
+#define HOOK_VAR_VOID2(type, name, fd, func, type1, arg1, type2, arg2) \
+    type name(type1 arg1, type2 arg2, ...) { \
+        va_list ap; \
+        va_start(ap, arg2); \
+        func(arg1, arg2, ap); \
+        va_end(ap); \
+    }
 
 #define HOOK_FD2(type, name, fd, type1, arg1, type2, arg2) \
     static type (*real_ ## name)(type1, type2); \
diff --git a/tests/Makefile.am b/tests/Makefile.am
index 80d0cdd..72e822a 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -12,6 +12,11 @@ check_PROGRAMS = example example_exec
 example_SOURCES = example.c
 example_exec_SOURCES = example_exec.c
 
+if HAVE_ERR_H
+    TESTS += test_err.sh
+    check_PROGRAMS += example_err
+    example_error_SOURCES = example_err.c
+endif
 if HAVE_ERROR_H
     TESTS += test_error.sh
     check_PROGRAMS += example_error
@@ -24,9 +29,11 @@ if HAVE_VFORK
 endif
 
 dist_check_SCRIPTS = $(TESTS) lib.sh
-dist_check_DATA = example.expected \
+dist_check_DATA = example.h \
+                  example.expected \
                   example_environment.expected \
                   example_environment_empty.expected \
+                  example_err.expected \
                   example_error.expected \
                   example_exec.expected \
                   example_noforce.sh \
diff --git a/tests/example.h b/tests/example.h
new file mode 100644
index 0000000..facbc30
--- /dev/null
+++ b/tests/example.h
@@ -0,0 +1,38 @@
+/*
+ * Helper functions/macros for example files.
+ *
+ * Copyright (C) 2013  Simon Ruderich
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+
+#define FORKED_TEST(pid) \
+    pid = fork(); \
+    if (pid == -1) { \
+        perror("fork"); \
+        exit(EXIT_FAILURE); \
+    } else if (pid != 0) { \
+        int status; \
+        if (waitpid(pid, &status, 0) == -1) { \
+            perror("waitpid"); \
+            exit(EXIT_FAILURE); \
+        } \
+        if (WIFEXITED(status)) { \
+            printf("exit code: %d\n", WEXITSTATUS(status)); \
+        } else { \
+            printf("child terminated!\n"); \
+        } \
+        fflush(stdout); \
+    } else
diff --git a/tests/example_err.c b/tests/example_err.c
new file mode 100644
index 0000000..90072c4
--- /dev/null
+++ b/tests/example_err.c
@@ -0,0 +1,51 @@
+/*
+ * Test err(), verr(), ... Non-standard, BSD only.
+ *
+ * Copyright (C) 2013  Simon Ruderich
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <config.h>
+
+#include <err.h>
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <unistd.h>
+
+#include "../src/compiler.h"
+#include "example.h"
+
+
+int main(int argc unused, char **argv unused) {
+    pid_t pid;
+
+    FORKED_TEST(pid) { errno = ENOMEM; err(0, "error: %s", "message"); }
+    FORKED_TEST(pid) { errno = ENOMEM; err(1, "error: %s", "message"); }
+
+    FORKED_TEST(pid) { errx(0, "error: %s", "message"); }
+    FORKED_TEST(pid) { errx(1, "error: %s", "message"); }
+
+    errno = ENOMEM;
+    warn("warning: %s", "message");
+    warnx("warning: %s", "message");
+
+    /* v*() functions are implicitly tested - the implementation uses them. */
+
+    printf("\n");
+    return EXIT_SUCCESS;
+}
diff --git a/tests/example_err.expected b/tests/example_err.expected
new file mode 100644
index 0000000..652cd81
--- /dev/null
+++ b/tests/example_err.expected
@@ -0,0 +1,11 @@
+>STDERR>example_err: error: message: Cannot allocate memory
+<STDERR<exit code: 0
+>STDERR>example_err: error: message: Cannot allocate memory
+<STDERR<exit code: 1
+>STDERR>example_err: error: message
+<STDERR<exit code: 0
+>STDERR>example_err: error: message
+<STDERR<exit code: 1
+>STDERR>example_err: warning: message: Cannot allocate memory
+<STDERR<>STDERR>example_err: warning: message
+<STDERR<
diff --git a/tests/test_err.sh b/tests/test_err.sh
new file mode 100755
index 0000000..fa16ebb
--- /dev/null
+++ b/tests/test_err.sh
@@ -0,0 +1,23 @@
+#!/bin/sh
+
+# Copyright (C) 2013  Simon Ruderich
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+
+test "x$srcdir" = x && srcdir=.
+. "$srcdir/lib.sh"
+
+test_program          example_err
+test_program_subshell example_err
-- 
2.44.1


From ca12529c8f3880c008212e97cf6b4b7d6981dec8 Mon Sep 17 00:00:00 2001
From: Simon Ruderich <simon@ruderich.org>
Date: Sat, 15 Jun 2013 03:23:53 +0200
Subject: [PATCH 15/16] hookmacros.h: Reduce duplication in macros.

Also preparation to add attributes to function declarations.
---
 src/hookmacros.h | 47 ++++++++++++++++++++++++-----------------------
 1 file changed, 24 insertions(+), 23 deletions(-)

diff --git a/src/hookmacros.h b/src/hookmacros.h
index 18a828e..8a05811 100644
--- a/src/hookmacros.h
+++ b/src/hookmacros.h
@@ -110,6 +110,9 @@
 #define HOOK_FUNC_DEF3(type, name, type1, arg1, type2, arg2, type3, arg3) \
     static type (*real_ ## name)(type1, type2, type3); \
     type name(type1 arg1, type2 arg2, type3 arg3)
+#define HOOK_FUNC_DEF4(type, name, type1, arg1, type2, arg2, type3, arg3, type4, arg4) \
+    static type (*real_ ## name)(type1, type2, type3, type4); \
+    type name(type1 arg1, type2 arg2, type3 arg3, type4 arg4)
 
 #define HOOK_FUNC_VAR_DEF2(type, name, type1, arg1, type2, arg2) \
     static type (*real_ ## name)(type1, type2, ...); \
@@ -118,37 +121,41 @@
 #define HOOK_FUNC_SIMPLE3(type, name, type1, arg1, type2, arg2, type3, arg3) \
     type name(type1 arg1, type2 arg2, type3 arg3)
 
+#define HOOK_FUNC_VAR_SIMPLE1(type, name, type1, arg1) \
+    type name(type1 arg1, ...)
+#define HOOK_FUNC_VAR_SIMPLE2(type, name, type1, arg1, type2, arg2) \
+    type name(type1 arg1, type2 arg2, ...)
+#define HOOK_FUNC_VAR_SIMPLE3(type, name, type1, arg1, type2, arg2, type3, arg3) \
+    type name(type1 arg1, type2 arg2, type3 arg3, ...)
+
 #define HOOK_VOID1(type, name, fd, type1, arg1) \
-    static type (*real_ ## name)(type1); \
-    type name(type1 arg1) { \
+    HOOK_FUNC_DEF1(type, name, type1, arg1) { \
         _HOOK_PRE_FD_(type, name, fd) \
         real_ ## name(arg1); \
         _HOOK_POST_FD_(fd) \
     }
 #define HOOK_VOID2(type, name, fd, type1, arg1, type2, arg2) \
-    static type (*real_ ## name)(type1, type2); \
-    type name(type1 arg1, type2 arg2) { \
+    HOOK_FUNC_DEF2(type, name, type1, arg1, type2, arg2) { \
         _HOOK_PRE_FD_(type, name, fd) \
         real_ ## name(arg1, arg2); \
         _HOOK_POST_FD_(fd) \
     }
 #define HOOK_VOID3(type, name, fd, type1, arg1, type2, arg2, type3, arg3) \
-    static type (*real_ ## name)(type1, type2, type3); \
-    type name(type1 arg1, type2 arg2, type3 arg3) { \
+    HOOK_FUNC_DEF3(type, name, type1, arg1, type2, arg2, type3, arg3) { \
         _HOOK_PRE_FD_(type, name, fd) \
         real_ ## name(arg1, arg2, arg3); \
         _HOOK_POST_FD_(fd) \
     }
 
 #define HOOK_VAR_VOID1(type, name, fd, func, type1, arg1) \
-    type name(type1 arg1, ...) { \
+    HOOK_FUNC_VAR_SIMPLE1(type, name, type1, arg1) { \
         va_list ap; \
         va_start(ap, arg1); \
         func(arg1, ap); \
         va_end(ap); \
     }
 #define HOOK_VAR_VOID2(type, name, fd, func, type1, arg1, type2, arg2) \
-    type name(type1 arg1, type2 arg2, ...) { \
+    HOOK_FUNC_VAR_SIMPLE2(type, name, type1, arg1, type2, arg2) { \
         va_list ap; \
         va_start(ap, arg2); \
         func(arg1, arg2, ap); \
@@ -156,51 +163,45 @@
     }
 
 #define HOOK_FD2(type, name, fd, type1, arg1, type2, arg2) \
-    static type (*real_ ## name)(type1, type2); \
-    type name(type1 arg1, type2 arg2) { \
+    HOOK_FUNC_DEF2(type, name, type1, arg1, type2, arg2) { \
         _HOOK_PRE_FD(type, name, fd) \
         result = real_ ## name(arg1, arg2); \
         _HOOK_POST_FD(fd) \
     }
 #define HOOK_FD3(type, name, fd, type1, arg1, type2, arg2, type3, arg3) \
-    static type (*real_ ## name)(type1, type2, type3); \
-    type name(type1 arg1, type2 arg2, type3 arg3) { \
+    HOOK_FUNC_DEF3(type, name, type1, arg1, type2, arg2, type3, arg3) { \
         _HOOK_PRE_FD(type, name, fd) \
         result = real_ ## name(arg1, arg2, arg3); \
         _HOOK_POST_FD(fd) \
     }
 
 #define HOOK_FILE1(type, name, file, type1, arg1) \
-    static type (*real_ ## name)(type1); \
-    type name(type1 arg1) { \
+    HOOK_FUNC_DEF1(type, name, type1, arg1) { \
         _HOOK_PRE_FILE(type, name, file) \
         result = real_ ## name(arg1); \
         _HOOK_POST_FILE(file) \
     }
 #define HOOK_FILE2(type, name, file, type1, arg1, type2, arg2) \
-    static type (*real_ ## name)(type1, type2); \
-    type name(type1 arg1, type2 arg2) { \
+    HOOK_FUNC_DEF2(type, name, type1, arg1, type2, arg2) { \
         _HOOK_PRE_FILE(type, name, file) \
         result = real_ ## name(arg1, arg2); \
         _HOOK_POST_FILE(file) \
     }
 #define HOOK_FILE3(type, name, file, type1, arg1, type2, arg2, type3, arg3) \
-    static type (*real_ ## name)(type1, type2, type3); \
-    type name(type1 arg1, type2 arg2, type3 arg3) { \
+    HOOK_FUNC_DEF3(type, name, type1, arg1, type2, arg2, type3, arg3) { \
         _HOOK_PRE_FILE(type, name, file) \
         result = real_ ## name(arg1, arg2, arg3); \
         _HOOK_POST_FILE(file) \
     }
 #define HOOK_FILE4(type, name, file, type1, arg1, type2, arg2, type3, arg3, type4, arg4) \
-    static type (*real_ ## name)(type1, type2, type3, type4); \
-    type name(type1 arg1, type2 arg2, type3 arg3, type4 arg4) { \
+    HOOK_FUNC_DEF4(type, name, type1, arg1, type2, arg2, type3, arg3, type4, arg4) { \
         _HOOK_PRE_FILE(type, name, file) \
         result = real_ ## name(arg1, arg2, arg3, arg4); \
         _HOOK_POST_FILE(file) \
     }
 
 #define HOOK_VAR_FILE1(type, name, file, func, type1, arg1) \
-    type name(type1 arg1, ...) { \
+    HOOK_FUNC_VAR_SIMPLE1(type, name, type1, arg1) { \
         va_list ap; \
         va_start(ap, arg1); \
         type result = func(arg1, ap); \
@@ -208,7 +209,7 @@
         return result; \
     }
 #define HOOK_VAR_FILE2(type, name, file, func, type1, arg1, type2, arg2) \
-    type name(type1 arg1, type2 arg2, ...) { \
+    HOOK_FUNC_VAR_SIMPLE2(type, name, type1, arg1, type2, arg2) { \
         va_list ap; \
         va_start(ap, arg2); \
         type result = func(arg1, arg2, ap); \
@@ -216,7 +217,7 @@
         return result; \
     }
 #define HOOK_VAR_FILE3(type, name, file, func, type1, arg1, type2, arg2, type3, arg3) \
-    type name(type1 arg1, type2 arg2, type3 arg3, ...) { \
+    HOOK_FUNC_VAR_SIMPLE3(type, name, type1, arg1, type2, arg2, type3, arg3) { \
         va_list ap; \
         va_start(ap, arg3); \
         type result = func(arg1, arg2, arg3, ap); \
-- 
2.44.1


From a58d1a9017a1a15a237f5b516fe2c44a0f01482e Mon Sep 17 00:00:00 2001
From: Simon Ruderich <simon@ruderich.org>
Date: Sat, 15 Jun 2013 03:36:50 +0200
Subject: [PATCH 16/16] Mark hooked functions as visibility(("protected")).

---
 src/compiler.h   | 9 +++++++++
 src/hookmacros.h | 9 +++++++++
 2 files changed, 18 insertions(+)

diff --git a/src/compiler.h b/src/compiler.h
index 85b58b1..d1c12dc 100644
--- a/src/compiler.h
+++ b/src/compiler.h
@@ -26,10 +26,19 @@
 # define always_inline __attribute__((always_inline))
 /* Unused parameter. */
 # define unused        __attribute__((unused))
+/* Mark the function protected, which means it can't be overwritten by other
+ * modules (libraries), e.g. with LD_PRELOAD); otherwise same as the default
+ * visibility. This causes the compiler not use the PLT (and no relocations)
+ * for local calls from inside this module; but the symbols are still
+ * exported. This is faster and in this case prevents useless lookups as we
+ * hook those functions and nobody else should modify them. Not strictly
+ * necessary, but nice to have. */
+# define visibility_protected __attribute__((visibility("protected")))
 #else
 # define noinline
 # define always_inline
 # define unused
+# define visibility_protected
 #endif
 
 /* Branch prediction information for the compiler. */
diff --git a/src/hookmacros.h b/src/hookmacros.h
index 8a05811..539d0d9 100644
--- a/src/hookmacros.h
+++ b/src/hookmacros.h
@@ -103,29 +103,38 @@
 
 #define HOOK_FUNC_DEF1(type, name, type1, arg1) \
     static type (*real_ ## name)(type1); \
+    type name(type1) visibility_protected; \
     type name(type1 arg1)
 #define HOOK_FUNC_DEF2(type, name, type1, arg1, type2, arg2) \
     static type (*real_ ## name)(type1, type2); \
+    type name(type1, type2) visibility_protected; \
     type name(type1 arg1, type2 arg2)
 #define HOOK_FUNC_DEF3(type, name, type1, arg1, type2, arg2, type3, arg3) \
     static type (*real_ ## name)(type1, type2, type3); \
+    type name(type1, type2, type3) visibility_protected; \
     type name(type1 arg1, type2 arg2, type3 arg3)
 #define HOOK_FUNC_DEF4(type, name, type1, arg1, type2, arg2, type3, arg3, type4, arg4) \
     static type (*real_ ## name)(type1, type2, type3, type4); \
+    type name(type1, type2, type3, type4) visibility_protected; \
     type name(type1 arg1, type2 arg2, type3 arg3, type4 arg4)
 
 #define HOOK_FUNC_VAR_DEF2(type, name, type1, arg1, type2, arg2) \
     static type (*real_ ## name)(type1, type2, ...); \
+    type name(type1, type2, ...) visibility_protected; \
     type name(type1 arg1, type2 arg2, ...)
 
 #define HOOK_FUNC_SIMPLE3(type, name, type1, arg1, type2, arg2, type3, arg3) \
+    type name(type1, type2, type3) visibility_protected; \
     type name(type1 arg1, type2 arg2, type3 arg3)
 
 #define HOOK_FUNC_VAR_SIMPLE1(type, name, type1, arg1) \
+    type name(type1, ...) visibility_protected; \
     type name(type1 arg1, ...)
 #define HOOK_FUNC_VAR_SIMPLE2(type, name, type1, arg1, type2, arg2) \
+    type name(type1, type2, ...) visibility_protected; \
     type name(type1 arg1, type2 arg2, ...)
 #define HOOK_FUNC_VAR_SIMPLE3(type, name, type1, arg1, type2, arg2, type3, arg3) \
+    type name(type1, type2, type3, ...) visibility_protected; \
     type name(type1 arg1, type2 arg2, type3 arg3, ...)
 
 #define HOOK_VOID1(type, name, fd, type1, arg1) \
-- 
2.44.1