[lttng-dev] [Babeltrace RFC PATCH 03/28] Move build-specific strerror_r to compat directory

[Ikaheimonen, JP]

Add a new source directory 'compat'.
In that directory, add a new file 'strlib.c'.
In that file, add a new function compat_strerror_r that encapsulates
the build-specific differences of strerror_r.
Where strerror_r is used, now use compat_strerror_r.
---
 Makefile.am                              |  2 +-
 compat/Makefile.am                       | 10 ++++++++++
 compat/compat_strlib.c                   | 17 +++++++++++++++++
 configure.ac                             |  1 +
 include/babeltrace/babeltrace-internal.h | 32 +++-----------------------------
 include/babeltrace/compat/string.h       |  9 +++++++++
 lib/Makefile.am                          |  3 ++-
 7 files changed, 43 insertions(+), 31 deletions(-)
 create mode 100644 compat/Makefile.am
 create mode 100644 compat/compat_strlib.c
 create mode 100644 include/babeltrace/compat/string.h

diff --git a/Makefile.am b/Makefile.am
index b25b58f..cdfad5a 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -2,7 +2,7 @@ AM_CFLAGS = $(PACKAGE_CFLAGS) -I$(top_srcdir)/include
 
 ACLOCAL_AMFLAGS = -I m4
 
-SUBDIRS = include types lib formats converter tests doc extras
+SUBDIRS = include types compat lib formats converter tests doc extras
 
 dist_doc_DATA = ChangeLog LICENSE mit-license.txt gpl-2.0.txt \
 		std-ext-lib.txt
diff --git a/compat/Makefile.am b/compat/Makefile.am
new file mode 100644
index 0000000..d756aa7
--- /dev/null
+++ b/compat/Makefile.am
@@ -0,0 +1,10 @@
+AM_CFLAGS = $(PACKAGE_CFLAGS) -I$(top_srcdir)/include
+
+lib_LTLIBRARIES = libcompat.la
+
+libcompat_la_SOURCES = \
+	compat_strlib.c
+
+libcompat_la_LDFLAGS = \
+	-Wl,--no-as-needed
+
diff --git a/compat/compat_strlib.c b/compat/compat_strlib.c
new file mode 100644
index 0000000..9aabb07
--- /dev/null
+++ b/compat/compat_strlib.c
@@ -0,0 +1,17 @@
+#include <babeltrace/compat/string.h>
+
+int compat_strerror_r(int errnum, char *buf, size_t buflen)
+{
+#if !defined(__linux__) || ((_POSIX_C_SOURCE >= 200112L || _XOPEN_SOURCE >= 600) && !defined(_GNU_SOURCE))
+/* XSI-compliant strerror_r */
+	return strerror_r(errnum, buf, buflen);
+#else
+/* GNU-compliant strerror_r */
+	char * retbuf;
+	retbuf = strerror_r(errnum, buf, buflen);
+	if (retbuf != buf)
+		strcpy(buf, retbuf);
+	return 0;
+#endif
+}
+
diff --git a/configure.ac b/configure.ac
index 83822d6..29366da 100644
--- a/configure.ac
+++ b/configure.ac
@@ -93,6 +93,7 @@ AC_SUBST(babeltracectfincludedir)
 AC_CONFIG_FILES([
 	Makefile
 	types/Makefile
+	compat/Makefile
 	formats/Makefile
 	formats/ctf/Makefile
 	formats/ctf/types/Makefile
diff --git a/include/babeltrace/babeltrace-internal.h b/include/babeltrace/babeltrace-internal.h
index 22866bc..35382de 100644
--- a/include/babeltrace/babeltrace-internal.h
+++ b/include/babeltrace/babeltrace-internal.h
@@ -27,7 +27,7 @@
 #include <stdio.h>
 #include <glib.h>
 #include <stdint.h>
-#include <string.h>
+#include <babeltrace/compat/string.h>
 
 #define PERROR_BUFLEN	200
 
@@ -81,46 +81,20 @@ extern int babeltrace_verbose, babeltrace_debug;
 		perrorstr,						\
 		## args)
 
-#if !defined(__linux__) || ((_POSIX_C_SOURCE >= 200112L || _XOPEN_SOURCE >= 600) && !defined(_GNU_SOURCE))
-
 #define _bt_printf_perror(fp, fmt, args...)				\
 	({								\
 		char buf[PERROR_BUFLEN] = "Error in strerror_r()";	\
-		strerror_r(errno, buf, sizeof(buf));			\
+		compat_strerror_r(errno, buf, sizeof(buf));			\
 		_bt_printfe(fp, "error", buf, fmt, ## args);		\
 	})
 
 #define _bt_printfl_perror(fp, lineno, fmt, args...)			\
 	({								\
 		char buf[PERROR_BUFLEN] = "Error in strerror_r()";	\
-		strerror_r(errno, buf, sizeof(buf));			\
+		compat_strerror_r(errno, buf, sizeof(buf));			\
 		_bt_printfle(fp, "error", lineno, buf, fmt, ## args);	\
 	})
 
-#else
-
-/*
- * Version using GNU strerror_r, for linux with appropriate defines.
- */
-
-#define _bt_printf_perror(fp, fmt, args...)				\
-	({								\
-		char *buf;						\
-		char tmp[PERROR_BUFLEN] = "Error in strerror_r()";	\
-		buf = strerror_r(errno, tmp, sizeof(tmp));		\
-		_bt_printfe(fp, "error", buf, fmt, ## args);		\
-	})
-
-#define _bt_printfl_perror(fp, lineno, fmt, args...)			\
-	({								\
-		char *buf;						\
-		char tmp[PERROR_BUFLEN] = "Error in strerror_r()";	\
-		buf = strerror_r(errno, tmp, sizeof(tmp));		\
-		_bt_printfle(fp, "error", lineno, buf, fmt, ## args);	\
-	})
-
-#endif
-
 /* printf without lineno information */
 #define printf_fatal(fmt, args...)					\
 	_bt_printf(stderr, "fatal", fmt, ## args)
diff --git a/include/babeltrace/compat/string.h b/include/babeltrace/compat/string.h
new file mode 100644
index 0000000..8591b7e
--- /dev/null
+++ b/include/babeltrace/compat/string.h
@@ -0,0 +1,9 @@
+#ifndef _BABELTRACE_COMPAT_STRING_H
+#define BABELTRACE_COMPAT_STRING_H
+
+#include <string.h>
+
+int compat_strerror_r(int errnum, char *buf, size_t buflen);
+
+#endif
+
diff --git a/lib/Makefile.am b/lib/Makefile.am
index 7ffb164..fa470c0 100644
--- a/lib/Makefile.am
+++ b/lib/Makefile.am
@@ -14,4 +14,5 @@ libbabeltrace_la_SOURCES = babeltrace.c \
 libbabeltrace_la_LDFLAGS = \
 	-Wl,--no-as-needed \
 	prio_heap/libprio_heap.la \
-	$(top_builddir)/types/libbabeltrace_types.la
+	$(top_builddir)/types/libbabeltrace_types.la \
+	$(top_builddir)/compat/libcompat.la
-- 
1.8.1.msysgit.1