main: open file once, in main, and log an error when we fail

5 files changed, 26 insertions, 22 deletions

diff --git a/jpg.c b/jpg.c
index a3797b1..cb013c3 100644
--- a/jpg.c
+++ b/jpg.c
@@ -24,7 +24,7 @@ error_exit(j_common_ptr cinfo)
 }
 
 pixman_image_t *
-jpg_load(const char *path)
+jpg_load(FILE *fp, const char *path)
 {
     struct jpeg_decompress_struct cinfo = {0};
     struct my_error_mgr err_handler;
@@ -32,9 +32,10 @@ jpg_load(const char *path)
     uint8_t *image_data = NULL;
     pixman_image_t *pix = NULL;
 
-    FILE *fp = fopen(path, "rb");
-    if (fp == NULL)
-        goto err;
+    if (fseek(fp, 0, SEEK_SET) < 0) {
+        LOG_ERRNO("%s: failed to seek to beginning of file", path);
+        return NULL;
+    }
 
     cinfo.err = jpeg_std_error(&err_handler.mgr);
     err_handler.mgr.error_exit = &error_exit;
@@ -96,7 +97,6 @@ jpg_load(const char *path)
 
     jpeg_finish_decompress(&cinfo);
     jpeg_destroy_decompress(&cinfo);
-    fclose(fp);
 
     pix = pixman_image_create_bits_no_clear(
         format, width, height, (uint32_t *)image_data, stride);
@@ -113,7 +113,5 @@ err:
         pixman_image_unref(pix);
     free(image_data);
     jpeg_destroy_decompress(&cinfo);
-    if (fp != NULL)
-        fclose(fp);
     return NULL;
 }
diff --git a/jpg.h b/jpg.h
index e61b8b2..90e4803 100644
--- a/jpg.h
+++ b/jpg.h
@@ -1,5 +1,6 @@
 #pragma once
 
+#include <stdio.h>
 #include <pixman.h>
 
-pixman_image_t *jpg_load(const char *path);
+pixman_image_t *jpg_load(FILE *fp, const char *path);
diff --git a/main.c b/main.c
index f52b8a9..6777949 100644
--- a/main.c
+++ b/main.c
@@ -318,25 +318,32 @@ main(int argc, const char *const *argv)
         return EXIT_FAILURE;
     }
 
+    setlocale(LC_CTYPE, "");
+    log_init(LOG_COLORIZE_AUTO, false, LOG_FACILITY_DAEMON, LOG_CLASS_WARNING);
+
     const char *image_path = argv[1];
     image = NULL;
 
+    FILE *fp = fopen(image_path, "rb");
+    if (fp == NULL) {
+        LOG_ERRNO("%s: failed to open", image_path);
+        return EXIT_FAILURE;
+    }
+
 #if defined(WBG_HAVE_JPG)
     if (image == NULL)
-        image = jpg_load(image_path);
+        image = jpg_load(fp, image_path);
 #endif
 #if defined(WBG_HAVE_PNG)
     if (image == NULL)
-        image = png_load(image_path);
+        image = png_load(fp, image_path);
 #endif
     if (image == NULL) {
         fprintf(stderr, "error: %s: failed to load\n", image_path);
+        fclose(fp);
         return EXIT_FAILURE;
     }
 
-    setlocale(LC_CTYPE, "");
-    log_init(LOG_COLORIZE_AUTO, false, LOG_FACILITY_DAEMON, LOG_CLASS_WARNING);
-
     display = wl_display_connect(NULL);
     assert(display != NULL);
 
@@ -436,5 +443,6 @@ main(int argc, const char *const *argv)
         pixman_image_unref(image);
     }
     log_deinit();
+    fclose(fp);
     return exit_code;
 }
diff --git a/png-wbg.h b/png-wbg.h
index bf15f9d..71e7dac 100644
--- a/png-wbg.h
+++ b/png-wbg.h
@@ -1,5 +1,6 @@
 #pragma once
 
+#include <stdio.h>
 #include <pixman.h>
 
-pixman_image_t *png_load(const char *path);
+pixman_image_t *png_load(FILE *fp, const char *path);
diff --git a/png.c b/png.c
index 8b38167..71a4f3f 100644
--- a/png.c
+++ b/png.c
@@ -15,20 +15,18 @@
 #include "stride.h"
 
 pixman_image_t *
-png_load(const char *path)
+png_load(FILE *fp, const char *path)
 {
     pixman_image_t *pix = NULL;
 
-    FILE *fp = NULL;
     png_structp png_ptr = NULL;
     png_infop info_ptr = NULL;
     png_bytepp row_pointers = NULL;
     uint8_t *image_data = NULL;
 
-    /* open file and test for it being a png */
-    if ((fp = fopen(path, "rb")) == NULL) {
-        //LOG_ERRNO("%s: failed to open", path);
-        goto err;
+    if (fseek(fp, 0, SEEK_SET) < 0) {
+        LOG_ERRNO("%s: failed to seek to beginning of file", path);
+        return NULL;
     }
 
     /* Verify PNG header */
@@ -136,8 +134,6 @@ err:
     free(row_pointers);
     if (png_ptr != NULL)
         png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
-    if (fp != NULL)
-        fclose(fp);
 
     return pix;
 }