picoproj: get rid of exit(), return more meaningful values to userspace

Maybe the values returned by picoproj will never be used, but it is
better to use a clean style in example code.

diff --git a/examples/picoproj.c b/examples/picoproj.c
index e1dc47a..9128538 100644 (file)
--- a/examples/picoproj.c
+++ b/examples/picoproj.c
@@ -28,6 +28,7 @@
 #include <sys/stat.h>
 #include <fcntl.h>
 #include <unistd.h>
+#include <errno.h>
 
 #include "am7xxx.h"
 
@@ -58,7 +59,6 @@ static void usage(char *name)
 int main(int argc, char *argv[])
 {
        int ret;
-       int exit_code = EXIT_SUCCESS;
        int opt;
 
        char filename[FILENAME_MAX] = {0};
@@ -83,7 +83,8 @@ int main(int argc, char *argv[])
                        device_index = atoi(optarg);
                        if (device_index < 0) {
                                fprintf(stderr, "Unsupported device index\n");
-                               exit(EXIT_FAILURE);
+                               ret = -EINVAL;
+                               goto out;
                        }
                        break;
                case 'f':
@@ -102,7 +103,8 @@ int main(int argc, char *argv[])
                                break;
                        default:
                                fprintf(stderr, "Unsupported format\n");
-                               exit(EXIT_FAILURE);
+                               ret = -EINVAL;
+                               goto out;
                        }
                        break;
                case 'l':
@@ -125,7 +127,8 @@ int main(int argc, char *argv[])
                        default:
                                fprintf(stderr, "Invalid power mode value, must be between %d and %d\n",
                                        AM7XXX_POWER_OFF, AM7XXX_POWER_TURBO);
-                               exit(EXIT_FAILURE);
+                               ret = -EINVAL;
+                               goto out;
                        }
                        break;
                case 'z':
@@ -140,48 +143,53 @@ int main(int argc, char *argv[])
                        default:
                                fprintf(stderr, "Invalid zoom mode value, must be between %d and %d\n",
                                        AM7XXX_ZOOM_ORIGINAL, AM7XXX_ZOOM_TEST);
-                               exit(EXIT_FAILURE);
+                               ret = -EINVAL;
+                               goto out;
                        }
                        break;
                case 'W':
                        width = atoi(optarg);
                        if (width < 0) {
                                fprintf(stderr, "Unsupported width\n");
-                               exit(EXIT_FAILURE);
+                               ret = -EINVAL;
+                               goto out;
                        }
                        break;
                case 'H':
                        height = atoi(optarg);
                        if (height < 0) {
                                fprintf(stderr, "Unsupported height\n");
-                               exit(EXIT_FAILURE);
+                               ret = -EINVAL;
+                               goto out;
                        }
                        break;
                case 'h':
                        usage(argv[0]);
-                       exit(EXIT_SUCCESS);
+                       ret = 0;
+                       goto out;
                default: /* '?' */
                        usage(argv[0]);
-                       exit(EXIT_FAILURE);
+                       ret = -EINVAL;
+                       goto out;
                }
        }
 
        if (filename[0] == '\0') {
                fprintf(stderr, "An image file MUST be specified with the -f option.\n\n");
                usage(argv[0]);
-               exit_code = EXIT_FAILURE;
+               ret = -EINVAL;
                goto out;
        }
 
        image_fp = fopen(filename, "rb");
        if (image_fp == NULL) {
                perror("fopen");
-               exit_code = EXIT_FAILURE;
+               ret = -EINVAL;
                goto out;
        }
-       if (fstat(fileno(image_fp), &st) < 0) {
+       ret = fstat(fileno(image_fp), &st);
+       if (ret < 0) {
                perror("fstat");
-               exit_code = EXIT_FAILURE;
                goto out_close_image_fp;
        }
        size = st.st_size;
@@ -189,7 +197,7 @@ int main(int argc, char *argv[])
        image = malloc(size * sizeof(unsigned char));
        if (image == NULL) {
                perror("malloc");
-               exit_code = EXIT_FAILURE;
+               ret = -ENOMEM;
                goto out_close_image_fp;
        }
 
@@ -202,13 +210,14 @@ int main(int argc, char *argv[])
                else
                        fprintf(stderr, "Unexpected error condition.\n");
 
+               if (ret >= 0)
+                       ret = -EINVAL;
                goto out_free_image;
        }
 
        ret = am7xxx_init(&ctx);
        if (ret < 0) {
                perror("am7xxx_init");
-               exit_code = EXIT_FAILURE;
                goto out_free_image;
        }
 
@@ -217,28 +226,24 @@ int main(int argc, char *argv[])
        ret = am7xxx_open_device(ctx, &dev, 0);
        if (ret < 0) {
                perror("am7xxx_open_device");
-               exit_code = EXIT_FAILURE;
                goto cleanup;
        }
 
        ret = am7xxx_close_device(dev);
        if (ret < 0) {
                perror("am7xxx_close_device");
-               exit_code = EXIT_FAILURE;
                goto cleanup;
        }
 
        ret = am7xxx_open_device(ctx, &dev, device_index);
        if (ret < 0) {
                perror("am7xxx_open_device");
-               exit_code = EXIT_FAILURE;
                goto cleanup;
        }
 
        ret = am7xxx_get_device_info(dev, &device_info);
        if (ret < 0) {
                perror("am7xxx_get_device_info");
-               exit_code = EXIT_FAILURE;
                goto cleanup;
        }
        printf("Native resolution: %dx%d\n",
@@ -247,14 +252,12 @@ int main(int argc, char *argv[])
        ret = am7xxx_set_zoom_mode(dev, zoom);
        if (ret < 0) {
                perror("am7xxx_set_zoom_mode");
-               exit_code = EXIT_FAILURE;
                goto cleanup;
        }
 
        ret = am7xxx_set_power_mode(dev, power_mode);
        if (ret < 0) {
                perror("am7xxx_set_power_mode");
-               exit_code = EXIT_FAILURE;
                goto cleanup;
        }
 
@@ -273,11 +276,10 @@ int main(int argc, char *argv[])
        ret = am7xxx_send_image(dev, format, width, height, image, (unsigned int)size);
        if (ret < 0) {
                perror("am7xxx_send_image");
-               exit_code = EXIT_FAILURE;
                goto cleanup;
        }
 
-       exit_code = EXIT_SUCCESS;
+       ret = 0;
 
 cleanup:
        am7xxx_shutdown(ctx);
@@ -286,10 +288,9 @@ out_free_image:
        free(image);
 
 out_close_image_fp:
-       ret = fclose(image_fp);
-       if (ret == EOF)
+       if (fclose(image_fp) == EOF)
                perror("fclose");
 
 out:
-       exit(exit_code);
+       return ret;
 }