[Libsysio-commit] HEAD: libsysio/src lseek.c

[Lee W. <lw...@us...>]

Update of /cvsroot/libsysio/libsysio/src
In directory sc8-pr-cvs1.sourceforge.net:/tmp/cvs-serv468/src

Modified Files:
	lseek.c 
Log Message:


Changes to support better detection of overflow in 32/64 mixed compiles.


Index: lseek.c
===================================================================
RCS file: /cvsroot/libsysio/libsysio/src/lseek.c,v
retrieving revision 1.25
retrieving revision 1.26
diff -u -w -b -B -p -r1.25 -r1.26
--- lseek.c	14 Oct 2004 14:59:29 -0000	1.25
+++ lseek.c	2 Aug 2005 21:57:09 -0000	1.26
@@ -46,6 +46,7 @@
 #include <assert.h>
 #include <sys/types.h>
 #include <sys/stat.h>
+#include <fcntl.h>
 #include <sys/queue.h>
 
 #include "sysio.h"
@@ -54,17 +55,31 @@
 
 #include "sysio-symbols.h"
 
+/*
+ * Test whether large file support on this file.
+ */
+#ifdef O_LARGEFILE
+#define _SEEK_MAX_TEST(fil) \
+	((fil)->f_flags & O_LARGEFILE)
+#else
+#define _SEEK_MAX_TEST(fil) \
+	(1)
+#endif
+/*
+ * Return max seek value for this file.
+ */
+#define _SEEK_MAX(fil) \
+	(_SEEK_MAX_TEST(fil) ? _SYSIO_OFF_T_MAX : LONG_MAX)
+
 static _SYSIO_OFF_T
-_sysio_lseek(int fd, _SYSIO_OFF_T offset, int whence)
+_sysio_lseek(struct file *fil,
+	     _SYSIO_OFF_T offset,
+	     int whence,
+	     _SYSIO_OFF_T max)
 {
-	struct file *fil;
 	_SYSIO_OFF_T off, pos;
 	struct intnl_stat stbuf;
 
-	fil = _sysio_fd_find(fd);
-	if (!fil)
-		return -EBADF;
-
 	off = -1;
 	switch (whence) {
 	
@@ -99,14 +114,8 @@ _sysio_lseek(int fd, _SYSIO_OFF_T offset
 	pos = off + offset;
 	if ((offset < 0 && -offset > off) || (offset > 0 && pos <= off))
 		return -EINVAL;
-
-#ifdef O_LARGEFILE
-	if (pos >= ((fil->f_flags & O_LARGEFILE) ? _SYSIO_OFF_T_MAX : LONG_MAX))
-		return -EOVERFLOW;
-#else
-	if (pos >= _SYSIO_OFF_T_MAX)
+	if (pos >= max)
 		return -EOVERFLOW;
-#endif
 	pos = (fil->f_ino->i_ops.inop_pos)(fil->f_ino, pos);
 	if (pos < 0)
 		return pos;
@@ -120,17 +129,18 @@ _sysio_lseek(int fd, _SYSIO_OFF_T offset
 extern off64_t
 SYSIO_INTERFACE_NAME(lseek64)(int fd, off64_t offset, int whence)
 {
-	_SYSIO_OFF_T off;
-	off_t	rtn;
+	struct file *fil;
+	off64_t	off;
 	SYSIO_INTERFACE_DISPLAY_BLOCK;
 
 	SYSIO_INTERFACE_ENTER;
-	off = _sysio_lseek(fd, offset, whence);
-	if (off < 0)
-		SYSIO_INTERFACE_RETURN((off_t )-1, (int )off);
-	rtn = (off64_t )off;
-	assert(rtn == off);
-	SYSIO_INTERFACE_RETURN(rtn, 0);
+	fil = _sysio_fd_find(fd);
+	if (!fil)
+		SYSIO_INTERFACE_RETURN((off64_t )-1, -EBADF);
+	off = _sysio_lseek(fil, offset, whence, _SEEK_MAX(fil));
+	SYSIO_INTERFACE_RETURN(off < 0 ? (off64_t )-1 : off,
+			       off < 0 ? (int )off : 0);
+
 }
 #ifdef __GLIBC__
 #undef __lseek64
@@ -149,12 +159,16 @@ sysio_sym_weak_alias(SYSIO_INTERFACE_NAM
 extern off_t
 SYSIO_INTERFACE_NAME(lseek)(int fd, off_t offset, int whence)
 {
+	struct file *fil;
 	_SYSIO_OFF_T off;
 	off_t	rtn;
 	SYSIO_INTERFACE_DISPLAY_BLOCK;
 
 	SYSIO_INTERFACE_ENTER;
-	off = _sysio_lseek(fd, offset, whence);
+	fil = _sysio_fd_find(fd);
+	if (!fil)
+		SYSIO_INTERFACE_RETURN((off_t )-1, -EBADF);
+	off = _sysio_lseek(fil, offset, whence, LONG_MAX);
 	if (off < 0)
 		SYSIO_INTERFACE_RETURN((off_t )-1, (int )off);
 	rtn = (off_t )off;
@@ -177,6 +191,7 @@ SYSIO_INTERFACE_NAME(llseek)(unsigned in
        loff_t *result __IS_UNUSED,
        unsigned int whence __IS_UNUSED)
 {
+	struct file *fil;
 	loff_t	off;
 	SYSIO_INTERFACE_DISPLAY_BLOCK;
 
@@ -184,6 +199,9 @@ SYSIO_INTERFACE_NAME(llseek)(unsigned in
 	 * This is just plain goofy.
 	 */
 	SYSIO_INTERFACE_ENTER;
+	fil = _sysio_fd_find(fd);
+	if (!fil)
+		SYSIO_INTERFACE_RETURN(-1, -EBADF);
 #if !_LARGEFILE64_SOURCE
 	if (offset_high) {
 		/*
@@ -197,7 +215,7 @@ SYSIO_INTERFACE_NAME(llseek)(unsigned in
 	off <<= 32;
 	off |= offset_low;
 #endif
-	off = _sysio_lseek(fd, off, whence);
+	off = _sysio_lseek(fil, off, whence, _SEEK_MAX(fil));
 	if (off < 0)
 		SYSIO_INTERFACE_RETURN((off_t )-1, (int )off);
 	*result = off;