Support loading image data from stdin

3 files changed, 36 insertions, 11 deletions

diff --git a/src/imv.c b/src/imv.c
index 656b3a5..368973b 100644
--- a/src/imv.c
+++ b/src/imv.c
@@ -75,6 +75,8 @@ struct imv {
   struct imv_commands *commands;
   struct imv_texture *texture;
   struct imv_viewport *view;
+  void *stdin_image_data;
+  size_t stdin_image_data_len;
   char *input_buffer;
   char *starting_path;
   struct pollfd stdin_fd;
@@ -121,6 +123,8 @@ struct imv *imv_create(void)
   imv->navigator = imv_navigator_create();
   imv->loader = imv_loader_create();
   imv->commands = imv_commands_create();
+  imv->stdin_image_data = NULL;
+  imv->stdin_image_data_len = 0;
   imv->input_buffer = NULL;
   imv->starting_path = NULL;
   imv->window = NULL;
@@ -154,6 +158,9 @@ void imv_free(struct imv *imv)
   imv_navigator_free(imv->navigator);
   imv_loader_free(imv->loader);
   imv_commands_free(imv->commands);
+  if(imv->stdin_image_data) {
+    free(imv->stdin_image_data);
+  }
   if(imv->input_buffer) {
     free(imv->input_buffer);
   }
@@ -265,7 +272,23 @@ bool imv_parse_args(struct imv *imv, int argc, char **argv)
     imv->paths_from_stdin = true;
   } else {
     /* otherwise, add the paths */
+    bool data_from_stdin = false;
     for(int i = 0; i < argc; ++i) {
+
+      /* Special case: '-' denotes reading image data from stdin */
+      if(!strcmp("-", argv[i])) {
+        if(imv->paths_from_stdin) {
+          fprintf(stderr, "Can't read paths AND image data from stdin. Aborting.\n");
+          return false;
+        } else if(data_from_stdin) {
+          fprintf(stderr, "Can't read image data from stdin twice. Aborting.\n");
+          return false;
+        }
+        data_from_stdin = true;
+
+        imv->stdin_image_data_len = read_from_stdin(&imv->stdin_image_data);
+      }
+
       imv_add_path(imv, argv[i]);
     }
   }
@@ -366,15 +389,14 @@ bool imv_run(struct imv *imv)
       imv_navigator_remove(imv->navigator, err_path);
 
       /* special case: the image came from stdin */
-      /* if (strncmp(err_path, "-", 2) == 0) { */
-      /*   free(stdin_buffer); */
-      /*   stdin_buffer_size = 0; */
-      /*   if (stdin_error != 0) { */
-      /*     errno = stdin_error; */
-      /*     perror("Failed to load image from standard input"); */
-      /*     errno = 0; */
-      /*   } */
-      /* } */
+      if(strncmp(err_path, "-", 2) == 0) {
+        if(imv->stdin_image_data) {
+          free(imv->stdin_image_data);
+          imv->stdin_image_data = NULL;
+          imv->stdin_image_data_len = 0;
+        }
+        fprintf(stderr, "Failed to load image from stdin.\n");
+      }
       free(err_path);
     }
 
@@ -400,7 +422,8 @@ bool imv_run(struct imv *imv)
           scaling_label[imv->scaling_mode]);
       imv_viewport_set_title(imv->view, title);
 
-      imv_loader_load(imv->loader, current_path, "", 0 /*stdin_buffer, stdin_buffer_size*/);
+      imv_loader_load(imv->loader, current_path,
+          imv->stdin_image_data, imv->stdin_image_data_len);
       imv->view->playing = true;
     }
 
diff --git a/src/loader.c b/src/loader.c
index e85050b..b21b140 100644
--- a/src/loader.c
+++ b/src/loader.c
@@ -98,6 +98,7 @@ void imv_loader_load(struct imv_loader *ldr, const char *path,
     ldr->buffer_size = buffer_size;
   } else if (ldr->fi_buffer != NULL) {
     FreeImage_CloseMemory(ldr->fi_buffer);
+    ldr->fi_buffer = NULL;
   }
   pthread_create(&ldr->bg_thread, NULL, &bg_new_img, ldr);
   pthread_mutex_unlock(&ldr->lock);
@@ -191,6 +192,7 @@ static void *bg_new_img(void *data)
     if (from_stdin) {
       pthread_mutex_lock(&ldr->lock);
       FreeImage_CloseMemory(ldr->fi_buffer);
+      ldr->fi_buffer = NULL;
       pthread_mutex_unlock(&ldr->lock);
     }
     error_occurred(ldr);
diff --git a/src/util.c b/src/util.c
index 9b2b867..71d4c14 100644
--- a/src/util.c
+++ b/src/util.c
@@ -24,7 +24,7 @@ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 size_t read_from_stdin(void **buffer) {
   size_t len = 0;
   ssize_t r;
-  size_t step = 1024; /* Arbitrary value of 1 KiB */
+  size_t step = 4096; /* Arbitrary value of 4 KiB */
   void *p;
 
   errno = 0; /* clear errno */