talloc: add defines and functions for TALLOC_MAJOR/MINOR_VERSION

We also use the major and minor versions in the TALLOC_MAGIC,
so that we can detect if two conflicting versions of talloc
are loaded in one process. In this case we use talloc_log() to
output a very useful debug message before we call
talloc_abort().

metze

lib/talloc/Makefile.in

@@ -16,7 +16,10 @@ CC = @CC@
 CFLAGS = @CFLAGS@ -DHAVE_CONFIG_H= -I. -I@srcdir@
 EXTRA_TARGETS = @DOC_TARGET@
 PICFLAG = @PICFLAG@
-PACKAGE_VERSION = @PACKAGE_VERSION@
+TALLOC_VERSION = @TALLOC_VERSION@
+TALLOC_VERSION_MAJOR = @TALLOC_VERSION_MAJOR@
+TALLOC_VERSION_MINOR = @TALLOC_VERSION_MINOR@
+TALLOC_VERSION_RELEASE = @TALLOC_VERSION_RELEASE@
 SHLIBEXT = @SHLIBEXT@
 SHLD = @SHLD@
 SHLD_FLAGS = @SHLD_FLAGS@

lib/talloc/configure.ac

@@ -4,6 +4,26 @@ AC_CONFIG_SRCDIR([talloc.c])
 AC_SUBST(datarootdir)
 AC_CONFIG_HEADER(config.h)
 
+TALLOC_VERSION=${PACKAGE_VERSION}
+TALLOC_VERSION_MAJOR=`echo ${PACKAGE_VERSION} | cut -d '.' -f1`
+TALLOC_VERSION_MINOR=`echo ${PACKAGE_VERSION} | cut -d '.' -f2`
+TALLOC_VERSION_RELEASE=`echo ${PACKAGE_VERSION} | cut -d '.' -f3`
+
+AC_SUBST(TALLOC_VERSION)
+AC_SUBST(TALLOC_VERSION_MAJOR)
+AC_SUBST(TALLOC_VERSION_MINOR)
+AC_SUBST(TALLOC_VERSION_RELEASE)
+
+AC_DEFINE_UNQUOTED(TALLOC_BUILD_VERSION_MAJOR,
+	[${TALLOC_VERSION_MAJOR}],
+	[talloc major version])
+AC_DEFINE_UNQUOTED(TALLOC_BUILD_VERSION_MINOR,
+	[${TALLOC_VERSION_MINOR}],
+	[talloc minor version])
+AC_DEFINE_UNQUOTED(TALLOC_BUILD_VERSION_RELEASE,
+	[${TALLOC_VERSION_RELEASE}],
+	[talloc release version])
+
 AC_LIBREPLACE_ALL_CHECKS
 
 AC_LD_PICFLAG

lib/talloc/talloc.c

@@ -33,15 +33,31 @@
 #include "replace.h"
 #include "talloc.h"
 
+#ifdef TALLOC_BUILD_VERSION_MAJOR
+#if (TALLOC_VERSION_MAJOR != TALLOC_BUILD_VERSION_MAJOR)
+#error "TALLOC_VERSION_MAJOR != TALLOC_BUILD_VERSION_MAJOR"
+#endif
+#endif
+
+#ifdef TALLOC_BUILD_VERSION_MINOR
+#if (TALLOC_VERSION_MINOR != TALLOC_BUILD_VERSION_MINOR)
+#error "TALLOC_VERSION_MINOR != TALLOC_BUILD_VERSION_MINOR"
+#endif
+#endif
+
 /* use this to force every realloc to change the pointer, to stress test
    code that might not cope */
 #define ALWAYS_REALLOC 0
 
 
 #define MAX_TALLOC_SIZE 0x10000000
-#define TALLOC_MAGIC_V1 0xe814ec70
-#define TALLOC_MAGIC_V2 0xe814ec80
-#define TALLOC_MAGIC    TALLOC_MAGIC_V2
+#define TALLOC_MAGIC_BASE 0xe814ec70
+#define TALLOC_MAGIC ( \
+	TALLOC_MAGIC_BASE + \
+	(TALLOC_VERSION_MAJOR << 12) + \
+	(TALLOC_VERSION_MINOR << 4) \
+)
+
 #define TALLOC_FLAG_FREE 0x01
 #define TALLOC_FLAG_LOOP 0x02
 #define TALLOC_FLAG_POOL 0x04		/* This is a talloc pool */
@@ -123,6 +139,16 @@ struct talloc_chunk {
 #define TC_HDR_SIZE ((sizeof(struct talloc_chunk)+15)&~15)
 #define TC_PTR_FROM_CHUNK(tc) ((void *)(TC_HDR_SIZE + (char*)tc))
 
+int talloc_version_major(void)
+{
+	return TALLOC_VERSION_MAJOR;
+}
+
+int talloc_version_minor(void)
+{
+	return TALLOC_VERSION_MINOR;
+}
+
 static void (*talloc_log_fn)(const char *message);
 
 void talloc_set_log_fn(void (*log_fn)(const char *message))
@@ -176,9 +202,15 @@ static void talloc_abort(const char *reason)
 	talloc_abort_fn(reason);
 }
 
-static void talloc_abort_magic_v1(void)
+static void talloc_abort_magic(unsigned magic)
 {
-	talloc_abort("Bad talloc magic value - old magic v1 used");
+	unsigned striped = magic - TALLOC_MAGIC_BASE;
+	unsigned major = (striped & 0xFFFFF000) >> 12;
+	unsigned minor = (striped & 0x00000FF0) >> 4;
+	talloc_log("Bad talloc magic[0x%08X/%u/%u] expected[0x%08X/%u/%u]\n",
+		   magic, major, minor,
+		   TALLOC_MAGIC, TALLOC_VERSION_MAJOR, TALLOC_VERSION_MINOR);
+	talloc_abort("Bad talloc magic value - wrong talloc version used/mixed");
 }
 
 static void talloc_abort_double_free(void)
@@ -197,8 +229,8 @@ static inline struct talloc_chunk *talloc_chunk_from_ptr(const void *ptr)
 	const char *pp = (const char *)ptr;
 	struct talloc_chunk *tc = discard_const_p(struct talloc_chunk, pp - TC_HDR_SIZE);
 	if (unlikely((tc->flags & (TALLOC_FLAG_FREE | ~0xF)) != TALLOC_MAGIC)) { 
-		if ((tc->flags & (~0xF)) == TALLOC_MAGIC_V1) {
-			talloc_abort_magic_v1();
+		if ((tc->flags & (~0xFFF)) == TALLOC_MAGIC_BASE) {
+			talloc_abort_magic(tc->flags & (~0xF));
 			return NULL;
 		}
 

lib/talloc/talloc.h

@@ -29,6 +29,12 @@
 #include <stdio.h>
 #include <stdarg.h>
 
+#define TALLOC_VERSION_MAJOR 2
+#define TALLOC_VERSION_MINOR 0
+
+int talloc_version_major(void);
+int talloc_version_minor(void);
+
 /* this is only needed for compatibility with the old talloc */
 typedef void TALLOC_CTX;
 

lib/talloc/talloc.mk

@@ -1,7 +1,7 @@
 TALLOC_OBJ = $(tallocdir)/talloc.o 
 
-TALLOC_SOLIB = libtalloc.$(SHLIBEXT).$(PACKAGE_VERSION)
-TALLOC_SONAME = libtalloc.$(SHLIBEXT).1
+TALLOC_SOLIB = libtalloc.$(SHLIBEXT).$(TALLOC_VERSION)
+TALLOC_SONAME = libtalloc.$(SHLIBEXT).$(TALLOC_VERSION_MAJOR)
 TALLOC_STLIB = libtalloc.a
 
 all:: $(TALLOC_STLIB) $(TALLOC_SOLIB) testsuite

lib/talloc/talloc.pc.in

@@ -5,7 +5,7 @@ includedir=@includedir@
 
 Name: talloc 
 Description: A hierarchical pool based memory system with destructors
-Version: @PACKAGE_VERSION@
+Version: @TALLOC_VERSION@
 Libs: -L${libdir} -ltalloc
 Cflags: -I${includedir} 
 URL: http://talloc.samba.org/