Save a couple of syscalls per session

Fix apparent new-session-files-were-not-locked bug

Replace %m with portable "%s", strerror(errno)

diff --git a/ext/session/config.m4 b/ext/session/config.m4
index ad22cda7214f4ca87155622e210cf3b54196082c..054996cd620cd9fb85c25ce4a0769c7b7fcbe19c 100644 (file)
--- a/ext/session/config.m4
+++ b/ext/session/config.m4
@@ -31,6 +31,7 @@ if test "$PHP_TRANS_SID" = "yes"; then
 fi
 
 if test "$PHP_SESSION" != "no"; then
+  AC_CHECK_FUNCS(pread pwrite)
   PHP_EXTENSION(session,$ext_shared)
   PHP_SUBST(SESSION_SHARED_LIBADD)
 fi

diff --git a/ext/session/mod_files.c b/ext/session/mod_files.c
index ab24ee6354b0a3cb4541cf84b63bf27eba990b31..11a6ccb3401890d848212c7bcf8ef7432d6a2c52 100644 (file)
--- a/ext/session/mod_files.c
+++ b/ext/session/mod_files.c
@@ -49,6 +49,7 @@ typedef struct {
        char *basedir;
        size_t basedir_len;
        int dirdepth;
+       size_t st_size;
 } ps_files;
 
 ps_module ps_mod_files = {
@@ -140,21 +141,18 @@ static void ps_files_open(ps_files *data, const char *key)
                
 #ifdef O_EXCL
                data->fd = VCWD_OPEN((buf, O_RDWR | O_BINARY));
-               if (data->fd == -1) {
-                       if (errno == ENOENT) {
-                               data->fd = VCWD_OPEN((buf, O_EXCL | O_RDWR | O_CREAT | O_BINARY, 0600));
-                       }
-               } else {
-                       flock(data->fd, LOCK_EX);
-               }
+               
+               if (data->fd == -1 && errno == ENOENT) 
+                       data->fd = VCWD_OPEN((buf, O_EXCL | O_RDWR | O_CREAT | O_BINARY, 0600));
 #else
                data->fd = VCWD_OPEN((buf, O_CREAT | O_RDWR | O_BINARY, 0600));
-               if (data->fd != -1)
-                       flock(data->fd, LOCK_EX);
 #endif
+               if (data->fd != -1) 
+                       flock(data->fd, LOCK_EX);
 
                if (data->fd == -1)
-                       php_error(E_WARNING, "open(%s, O_RDWR) failed: %m (%d)", buf, errno);
+                       php_error(E_WARNING, "open(%s, O_RDWR) failed: %s (%d)", buf, 
+                                       strerror(errno), errno);
        }
 }
 
@@ -171,7 +169,7 @@ static int ps_files_cleanup_dir(const char *dirname, int maxlifetime)
 
        dir = opendir(dirname);
        if (!dir) {
-               php_error(E_NOTICE, "ps_files_cleanup_dir: opendir(%s) failed: %m (%d)\n", dirname, errno);
+               php_error(E_NOTICE, "ps_files_cleanup_dir: opendir(%s) failed: %s (%d)\n", dirname, strerror(errno), errno);
                return (0);
        }
 
@@ -248,7 +246,7 @@ PS_CLOSE_FUNC(files)
 
 PS_READ_FUNC(files)
 {
-       int n;
+       ssize_t n;
        struct stat sbuf;
        PS_FILES_DATA;
 
@@ -259,12 +257,15 @@ PS_READ_FUNC(files)
        if (fstat(data->fd, &sbuf))
                return FAILURE;
        
-       lseek(data->fd, 0, SEEK_SET);
-
-       *vallen = sbuf.st_size;
+       data->st_size = *vallen = sbuf.st_size;
        *val = emalloc(sbuf.st_size);
 
+#ifdef HAVE_PREAD
+       n = pread(data->fd, *val, sbuf.st_size, 0);
+#else
+       lseek(data->fd, 0, SEEK_SET);
        n = read(data->fd, *val, sbuf.st_size);
+#endif
        if (n != sbuf.st_size) {
                efree(*val);
                return FAILURE;
@@ -275,16 +276,30 @@ PS_READ_FUNC(files)
 
 PS_WRITE_FUNC(files)
 {
+       ssize_t n;
        PS_FILES_DATA;
 
        ps_files_open(data, key);
        if (data->fd < 0)
                return FAILURE;
 
-       ftruncate(data->fd, 0);
+       /* 
+        * truncate file, if the amount of new data is smaller than
+        * the existing data set.
+        */
+       
+       if (vallen < data->st_size)
+               ftruncate(data->fd, 0);
+
+#ifdef HAVE_PWRITE
+       n = pwrite(data->fd, val, vallen, 0);
+#else
        lseek(data->fd, 0, SEEK_SET);
-       if (write(data->fd, val, vallen) != vallen) {
-               php_error(E_WARNING, "write failed: %m (%d)", errno);
+       n = write(data->fd, val, vallen);
+#endif
+
+       if (n != vallen) {
+               php_error(E_WARNING, "write failed: %s (%d)", strerror(errno), errno);
                return FAILURE;
        }