Prompt user before doing anything

writeimg.c

@@ -29,6 +29,23 @@
 
 #define BYTES_TO_MIB(bts) ((double)bts / (1024 * 1024))
 
+#define BAR_WIDTH 50
+
+void print_progress(int current, int total) {
+    float fraction = (float)current / total;
+    int   filled = (int)(fraction * BAR_WIDTH);
+
+    printf("\r[");
+    for (int i = 0; i < BAR_WIDTH; i++) {
+        if (i < filled)
+            putchar('#');
+        else
+            putchar(' ');
+    }
+    printf("] %3d%%", (int)(fraction * 100));
+    fflush(stdout);
+}
+
 // clang-format off
 const char help[] =
     "Usage:\n"
@@ -74,16 +91,24 @@ int perform_write(write_job_t *job) {
     int block_fd = open(job->dev_name, O_RDWR);
     int file_fd = open(job->filename, O_RDONLY);
 
+    assert(block_fd >= 0);
+    assert(file_fd >= 0);
+
     /* TODO: Checks */
     assert(job->bufsize >= job->block_size);
 
     int    crc = crc32_init();
+    size_t b_written = 0;
 
     while (!job->verify_only) {
         ssize_t read_bytes = read(file_fd, job->buffer, job->block_size);
+        assert(read_bytes >= 0);
+
         if (read_bytes == 0) {
             fsync(block_fd);
             crc = crc32_finalize(crc);
+            printf("\nWriting done...\n");
+            assert(job->total_bytes == b_written);
             break; /* Finished */
         }
 
@@ -101,6 +126,7 @@ int perform_write(write_job_t *job) {
             perror("Write");
             exit(EXIT_FAILURE);
         }
+        print_progress(b_written += written_bytes, job->total_bytes);
     }
 
     lseek(block_fd, 0, SEEK_SET);
@@ -110,6 +136,7 @@ int perform_write(write_job_t *job) {
     memset(job->buffer2, 0, BLOCKSIZE);
 
     int crc_back = crc32_init();
+    b_written = 0;
 
     while (1) {
         ssize_t read_file = read(file_fd, job->buffer2, job->block_size);
@@ -122,10 +149,13 @@ int perform_write(write_job_t *job) {
         if (read_file == 0) {
             crc_back = crc32_finalize(crc_back);
             assert(crc_back == crc);
+            assert(job->total_bytes == b_written);
+            printf("\nVerification done!\n");
             break;
         }
 
         crc_back = crc32_update(crc_back, job->buffer, read_file);
+        print_progress(b_written += read_block, job->total_bytes);
 
         int cmp = memcmp((const void *)job->buffer2, (const void *)job->buffer, (size_t)read_file);
         if (0 != cmp) {
@@ -202,10 +232,26 @@ int main(int argc, char *argv[]) {
         exit(EXIT_FAILURE);
     }
 
+    /* Seems to be the cleanest way to check for write perm on a blockdev */
+    int fd = open(wjob.dev_name, O_WRONLY);
+    if (fd < 0) {
+        printf("Cannot write to \"%s\", do you have write permissions?\n", wjob.dev_name);
+        exit(1);
+    }
+    close(fd);
+
     printf("Writing %s to %s\n", wjob.filename, wjob.dev_name);
 
+    printf("Is this okay? (y/n): ");
+    fflush(stdout);
+    if ('y' != getchar()) {
+        exit(0);
+    }
+
     wjob.buffer = malloc(BLOCKSIZE);
     wjob.buffer2 = malloc(BLOCKSIZE);
+    assert(wjob.buffer);
+    assert(wjob.buffer2);
 
     wjob.bufsize = BLOCKSIZE;
     wjob.block_size = BLOCKSIZE;