omap_lcdc: omap_ppm_save(): add error handling

Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>

hw/omap_lcdc.c

@@ -224,18 +224,24 @@ static void omap_update_display(void *opaque)
     omap_lcd->invalidate = 0;
 }
 
-static int omap_ppm_save(const char *filename, uint8_t *data,
-                    int w, int h, int linesize)
+static void omap_ppm_save(const char *filename, uint8_t *data,
+                    int w, int h, int linesize, Error **errp)
 {
     FILE *f;
     uint8_t *d, *d1;
     unsigned int v;
-    int y, x, bpp;
+    int ret, y, x, bpp;
 
     f = fopen(filename, "wb");
-    if (!f)
-        return -1;
-    fprintf(f, "P6\n%d %d\n%d\n", w, h, 255);
+    if (!f) {
+        error_setg(errp, "failed to open file '%s': %s", filename,
+                   strerror(errno));
+        return;
+    }
+    ret = fprintf(f, "P6\n%d %d\n%d\n", w, h, 255);
+    if (ret < 0) {
+        goto write_err;
+    }
     d1 = data;
     bpp = linesize / w;
     for (y = 0; y < h; y ++) {
@@ -244,24 +250,49 @@ static int omap_ppm_save(const char *filename, uint8_t *data,
             v = *(uint32_t *) d;
             switch (bpp) {
             case 2:
-                fputc((v >> 8) & 0xf8, f);
-                fputc((v >> 3) & 0xfc, f);
-                fputc((v << 3) & 0xf8, f);
+                ret = fputc((v >> 8) & 0xf8, f);
+                if (ret == EOF) {
+                    goto write_err;
+                }
+                ret = fputc((v >> 3) & 0xfc, f);
+                if (ret == EOF) {
+                    goto write_err;
+                }
+                ret = fputc((v << 3) & 0xf8, f);
+                if (ret == EOF) {
+                    goto write_err;
+                }
                 break;
             case 3:
             case 4:
             default:
-                fputc((v >> 16) & 0xff, f);
-                fputc((v >> 8) & 0xff, f);
-                fputc((v) & 0xff, f);
+                ret = fputc((v >> 16) & 0xff, f);
+                if (ret == EOF) {
+                    goto write_err;
+                }
+                ret = fputc((v >> 8) & 0xff, f);
+                if (ret == EOF) {
+                    goto write_err;
+                }
+                ret = fputc((v) & 0xff, f);
+                if (ret == EOF) {
+                    goto write_err;
+                }
                 break;
             }
             d += bpp;
         }
         d1 += linesize;
     }
+out:
     fclose(f);
-    return 0;
+    return;
+
+write_err:
+    error_setg(errp, "failed to write to file '%s': %s", filename,
+               strerror(errno));
+    unlink(filename);
+    goto out;
 }
 
 static void omap_screen_dump(void *opaque, const char *filename, bool cswitch,
@@ -273,7 +304,7 @@ static void omap_screen_dump(void *opaque, const char *filename, bool cswitch,
     if (omap_lcd && ds_get_data(omap_lcd->state))
         omap_ppm_save(filename, ds_get_data(omap_lcd->state),
                     omap_lcd->width, omap_lcd->height,
-                    ds_get_linesize(omap_lcd->state));
+                    ds_get_linesize(omap_lcd->state), errp);
 }
 
 static void omap_invalidate_display(void *opaque) {