Update documentation.

[coloredstderr/coloredstderr.git] / src / coloredstderr.c

diff --git a/src/coloredstderr.c b/src/coloredstderr.c
index eb9d92cc3c1148d6160e87c4aade4171d8fd2c91..2640410aa040a4f72b5c6d24a6aa7facc780d75d 100644 (file)
--- a/src/coloredstderr.c
+++ b/src/coloredstderr.c
@@ -36,8 +36,12 @@
 #include <stdarg.h>
 #include <stdio.h>
 #include <string.h>
+#include <sys/stat.h>
 #include <unistd.h>
 
+#ifdef HAVE_ERR_H
+# include <err.h>
+#endif
 #ifdef HAVE_ERROR_H
 # include <error.h>
 #endif
@@ -45,11 +49,12 @@
 # include <libio.h>
 #endif
 
-/* Conflicting declaration in glibc. */
+/* The following functions may be macros. Undefine them or they cause build
+ * failures when used in our hook macros below. */
+
+/* In glibc, real fwrite_unlocked() is called in macro. */
 #undef fwrite_unlocked
-/* These functions may be macros when compiling with hardening flags (fortify)
- * which cause build failures when used in our hook macros below. Observed
- * with Clang on Debian Wheezy. */
+/* In Clang when compiling with hardening flags (fortify) on Debian Wheezy. */
 #undef printf
 #undef fprintf
 
@@ -256,8 +261,14 @@ HOOK_FILE2(int, putc_unlocked, stream,
            int, c, FILE *, stream)
 HOOK_FILE1(int, putchar_unlocked, stdout,
            int, c)
-/* glibc defines (_IO_)putc_unlocked() to __overflow() in some cases. */
+/* glibc defines (_IO_)putc_unlocked() to a macro which either updates the
+ * output buffer or calls __overflow(). As this code is inlined we can't
+ * handle the first case, but if __overflow() is called we can color that
+ * part. As writes to stderr are never buffered, __overflow() is always called
+ * and everything works fine. This is only a problem if stdout is dupped to
+ * stderr (which shouldn't be the case too often). */
 #ifdef HAVE_STRUCT__IO_FILE__FILENO
+/* _IO_FILE is glibc's representation of FILE. */
 HOOK_FD2(int, __overflow, f->_fileno, _IO_FILE *, f, int, ch)
 #endif
 
@@ -265,6 +276,33 @@ 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,