Avoid multiple stat() calls for same file

As a side effect we can also not use the dirent.d_type field

https://bugs.freedesktop.org/show_bug.cgi?id=68525

3 files changed, 32 insertions, 12 deletions

diff --git a/common/compat.c b/common/compat.c
index d813236..9aa556a 100644
--- a/common/compat.c
+++ b/common/compat.c
@@ -182,10 +182,11 @@ struct _p11_mmap {
 
 p11_mmap *
 p11_mmap_open (const char *path,
+               struct stat *sb,
                void **data,
                size_t *size)
 {
-	struct stat sb;
+	struct stat stb;
 	p11_mmap *map;
 
 	map = calloc (1, sizeof (p11_mmap));
@@ -198,13 +199,24 @@ p11_mmap_open (const char *path,
 		return NULL;
 	}
 
-	if (fstat (map->fd, &sb) < 0) {
+	if (sb == NULL) {
+		sb = &stb;
+		if (fstat (map->fd, &stb) < 0) {
+			close (map->fd);
+			free (map);
+			return NULL;
+		}
+	}
+
+	/* Workaround for broken ZFS on Linux */
+	if (S_ISDIR (sb->st_mode)) {
+		errno = EISDIR;
 		close (map->fd);
 		free (map);
 		return NULL;
 	}
 
-	map->size = sb.st_size;
+	map->size = sb->st_size;
 	map->data = mmap (NULL, map->size, PROT_READ, MAP_PRIVATE, map->fd, 0);
 	if (map->data == NULL) {
 		close (map->fd);
@@ -289,6 +301,7 @@ struct _p11_mmap {
 
 p11_mmap *
 p11_mmap_open (const char *path,
+               struct stat *sb,
                void **data,
                size_t *size)
 {
@@ -315,14 +328,18 @@ p11_mmap_open (const char *path,
 		return NULL;
 	}
 
-	if (!GetFileSizeEx (map->file, &large)) {
-		errn = GetLastError ();
-		CloseHandle (map->file);
-		free (map);
-		SetLastError (errn);
-		if (errn == ERROR_ACCESS_DENIED)
-			errno = EPERM;
-		return NULL;
+	if (sb == NULL) {
+		if (!GetFileSizeEx (map->file, &large)) {
+			errn = GetLastError ();
+			CloseHandle (map->file);
+			free (map);
+			SetLastError (errn);
+			if (errn == ERROR_ACCESS_DENIED)
+				errno = EPERM;
+			return NULL;
+		}
+	} else {
+		large.QuadPart = sb->st_size;
 	}
 
 	mapping = CreateFileMapping (map->file, NULL, PAGE_READONLY, 0, 0, NULL);
diff --git a/common/compat.h b/common/compat.h
index b593cf6..d7fe414 100644
--- a/common/compat.h
+++ b/common/compat.h
@@ -38,6 +38,7 @@
 #include "config.h"
 
 #include <sys/types.h>
+#include <sys/stat.h>
 
 #ifdef _GNU_SOURCE
 #error Make the crap stop. _GNU_SOURCE is completely unportable and breaks all sorts of behavior
@@ -158,6 +159,7 @@ void      p11_dl_close       (void * dl);
 typedef struct _p11_mmap p11_mmap;
 
 p11_mmap *  p11_mmap_open   (const char *path,
+                             struct stat *sb,
                              void **data,
                              size_t *size);
 
@@ -220,6 +222,7 @@ char * p11_dl_error (void);
 typedef struct _p11_mmap p11_mmap;
 
 p11_mmap *  p11_mmap_open   (const char *path,
+                             struct stat *sb,
                              void **data,
                              size_t *size);
 
diff --git a/common/test.c b/common/test.c
index daee663..83e9644 100644
--- a/common/test.c
+++ b/common/test.c
@@ -350,7 +350,7 @@ copy_file (const char *input,
 	ssize_t written;
 	size_t size;
 
-	mmap = p11_mmap_open (input, (void **)&data, &size);
+	mmap = p11_mmap_open (input, NULL, (void **)&data, &size);
 	assert (mmap != NULL);
 
 	while (size > 0) {