Add command to enable/disable dummy read

src/camogm.c

@@ -160,6 +160,7 @@ inline void set_chn_state(camogm_state *s, unsigned int port, unsigned int new_s
 inline int is_chn_active(camogm_state *s, unsigned int port);
 void clean_up(camogm_state *state);
 static void camogm_err_stat(const camogm_state *state, int port, FILE *f, bool xml);
+static void camogm_set_dummy_read(camogm_state *state, int d);
 
 void put_uint16(void *buf, u_int16_t val)
 {
@@ -268,6 +269,8 @@ void camogm_init(camogm_state *state, char *pipe_name, uint16_t port_num)
 	state->writer_params.data_ready = false;
 	state->writer_params.exit_thread = false;
 	state->writer_params.state = STATE_STOPPED;
+
+	camogm_set_dummy_read(state, 0);
 }
 
 /**
@@ -846,6 +849,12 @@ void  camogm_set_ignore_fps(camogm_state *state, int d)
 	state->ignore_fps =   d ? 1 : 0;
 }
 
+void camogm_set_dummy_read(camogm_state *state, int d)
+{
+	state->writer_params.dummy_read = d ? true : false;
+	D6(fprintf(debug_file, "Set dummy read flag = %d\n", state->writer_params.dummy_read));
+}
+
 /**
  * @brief Set file name prefix or raw device file name.
  * @param[in]   state   a pointer to a structure containing current state
@@ -1484,6 +1493,9 @@ int parse_cmd(camogm_state *state, FILE* npipe)
 			D0(fprintf(debug_file, "Reading thread is not running, nothing to stop\n"));
 		}
 		return 29;
+	} else if (strcmp(cmd, "dummy_read") == 0) {
+		if ((args) && ((d = strtol(args, NULL, 10)) > 0)) camogm_set_dummy_read(state, d);
+		return 30;
 	}
 
 	return -1;

src/camogm.h

@@ -162,6 +162,7 @@ struct writer_params {
 	uint64_t lba_end;                                       ///< disk last LBA
 
 	time_t stat_update;                                     ///< time when status file was updated
+	bool dummy_read;                                        ///< inable dummy read cycle (debug feature)
 };
 /**
  * @struct camogm_state

src/camogm_jpeg.c

@@ -426,17 +426,20 @@ void *jpeg_writer(void *thread_args)
 			process = false;
 		}
 		if (params->data_ready) {
-			/* dummy read cycle from (approximately) the beginning of previous frame */
-			ssize_t data_len;
-			off64_t curr_offset = lseek64(state->writer_params.blockdev_fd, 0, SEEK_CUR);
-			off64_t offset = lba_to_offset(state->writer_params.lba_current - state->writer_params.lba_start) - state->rawdev.last_jpeg_size;
-			offset = offset / PHY_BLOCK_SIZE;
-			lseek64(state->writer_params.blockdev_fd, offset, SEEK_SET);
-			data_len = read(state->writer_params.blockdev_fd, dummy_buff, PHY_BLOCK_SIZE);
-			if (data_len < PHY_BLOCK_SIZE) {
-				D6(fprintf(debug_file, "Dummy read error: requested %d, read %d, %s\n", PHY_BLOCK_SIZE, data_len, strerror(errno)));
+			/* dummy read cycle from (approximately) the beginning of previous frame;
+			 * this is a debug feature used to find disk errors */
+			if (state->writer_params.dummy_read) {
+				ssize_t data_len;
+				off64_t curr_offset = lseek64(state->writer_params.blockdev_fd, 0, SEEK_CUR);
+				off64_t offset = lba_to_offset(state->writer_params.lba_current - state->writer_params.lba_start) - state->rawdev.last_jpeg_size;
+				offset = offset / PHY_BLOCK_SIZE;
+				lseek64(state->writer_params.blockdev_fd, offset, SEEK_SET);
+				data_len = read(state->writer_params.blockdev_fd, dummy_buff, PHY_BLOCK_SIZE);
+				if (data_len < PHY_BLOCK_SIZE) {
+					D6(fprintf(debug_file, "Dummy read error: requested %d, read %d, %s\n", PHY_BLOCK_SIZE, data_len, strerror(errno)));
+				}
+				lseek64(state->writer_params.blockdev_fd, curr_offset, SEEK_SET);
 			}
-			lseek64(state->writer_params.blockdev_fd, curr_offset, SEEK_SET);
 			/* end of dummy read cycle */
 
 			l = 0;

src/camogmgui/camogm_interface.php

@@ -609,6 +609,7 @@ else
 			fprintf($fcmd, "prefix=%s;\n", $prefix);
 			setcookie("directory", $prefix);
 			break;
+			
 		case "set_debuglev":
 			$debuglev = $_GET['debuglev'];
 			fprintf($fcmd, "debuglev=%s;\n", $debuglev);
@@ -668,20 +669,24 @@ else
 			exec('aplay '.$soundfile);
 			break;
 		case "setmov":
-			exec('echo "format=mov;" > /var/state/camogm_cmd'); // Set quicktime *.mov as default format after startup.
-			exec('echo "save_gp=1;\n" > /var/state/camogm_cmd'); // enable calculation of free/used buffer space
+			exec('echo "format=mov;" > '.$cmd_pipe); // Set quicktime *.mov as default format after startup.
+			exec('echo "save_gp=1;\n" > '.$cmd_pipe); // enable calculation of free/used buffer space
 			break;
 		case "setjpeg":
-			exec('echo "format=jpg;" > /var/state/camogm_cmd'); // Set quicktime *.mov as default format after startup.
-			exec('echo "save_gp=1;\n" > /var/state/camogm_cmd'); // enable calculation of free/used buffer space
+			exec('echo "format=jpg;" > '.$cmd_pipe); // Set quicktime *.mov as default format after startup.
+			exec('echo "save_gp=1;\n" > '.$cmd_pipe); // enable calculation of free/used buffer space
 			break;
-                case "setrawdevpath":
-                        $rawdev_path = $_GET['path'];
-                        exec('echo "rawdev_path='.$rawdev_path.';" > /var/state/camogm_cmd');
-                        break;
+		case "setrawdevpath":
+				$rawdev_path = $_GET['path'];
+				exec('echo "rawdev_path='.$rawdev_path.';" > '.$cmd_pipe);
+				break;
 		case "gettime":
 			echo elphel_get_fpga_time();
 			break;
+		case "set_dummy_read":
+			$dummy_read = $_GET["dummy_read"];
+			exec('echo "dummy_read='.$dummy_read.';" > '.$cmd_pipe);
+			break;
 	}
 	if ($fcmd)
 		fclose($fcmd);