jtag: drivers: with pointers, use NULL instead of 0

Don't compare pointers with 0, use NULL when needed.
Don't assign pointer to 0, use NULL.
Don't pass 0 ad pointer argument, pass NULL.

While there, check for return value from malloc(), replace an
assert() with a LOG_ERROR(), drop a useless cast.

Detected through 'sparse' tool.

Change-Id: Ia7cf52221b12198aba1a07ebdfaf57ce341d5699
Signed-off-by: Antonio Borneo <borneo.antonio@gmail.com>
Reviewed-on: https://review.openocd.org/c/openocd/+/7592
Tested-by: jenkins

14 files changed, 40 insertions, 32 deletions

diff --git a/src/jtag/drivers/arm-jtag-ew.c b/src/jtag/drivers/arm-jtag-ew.c
index 7db3c7b..a372720 100644
--- a/src/jtag/drivers/arm-jtag-ew.c
+++ b/src/jtag/drivers/arm-jtag-ew.c
@@ -213,7 +213,7 @@ static int armjtagew_init(void)
 
 	armjtagew_handle = armjtagew_usb_open();
 
-	if (armjtagew_handle == 0) {
+	if (!armjtagew_handle) {
 		LOG_ERROR(
 			"Cannot find ARM-JTAG-EW Interface! Please check connection and permissions.");
 		return ERROR_JTAG_INIT_FAILED;
diff --git a/src/jtag/drivers/at91rm9200.c b/src/jtag/drivers/at91rm9200.c
index 08daa00..ba9ee5e 100644
--- a/src/jtag/drivers/at91rm9200.c
+++ b/src/jtag/drivers/at91rm9200.c
@@ -107,7 +107,7 @@ static int at91rm9200_quit(void);
 static struct bitbang_interface at91rm9200_bitbang = {
 	.read = at91rm9200_read,
 	.write = at91rm9200_write,
-	.blink = 0
+	.blink = NULL,
 };
 
 static bb_value_t at91rm9200_read(void)
@@ -157,8 +157,12 @@ COMMAND_HANDLER(at91rm9200_handle_device_command)
 		return ERROR_COMMAND_SYNTAX_ERROR;
 
 	/* only if the device name wasn't overwritten by cmdline */
-	if (at91rm9200_device == 0) {
+	if (!at91rm9200_device) {
 		at91rm9200_device = malloc(strlen(CMD_ARGV[0]) + sizeof(char));
+		if (!at91rm9200_device) {
+			LOG_ERROR("Out of memory");
+			return ERROR_FAIL;
+		}
 		strcpy(at91rm9200_device, CMD_ARGV[0]);
 	}
 
diff --git a/src/jtag/drivers/ep93xx.c b/src/jtag/drivers/ep93xx.c
index 5cb6dff..c3e841d 100644
--- a/src/jtag/drivers/ep93xx.c
+++ b/src/jtag/drivers/ep93xx.c
@@ -58,7 +58,7 @@ struct adapter_driver ep93xx_adapter_driver = {
 static struct bitbang_interface ep93xx_bitbang = {
 	.read = ep93xx_read,
 	.write = ep93xx_write,
-	.blink = 0,
+	.blink = NULL,
 };
 
 static bb_value_t ep93xx_read(void)
diff --git a/src/jtag/drivers/ft232r.c b/src/jtag/drivers/ft232r.c
index 816b2d0..1d73af4 100644
--- a/src/jtag/drivers/ft232r.c
+++ b/src/jtag/drivers/ft232r.c
@@ -235,7 +235,7 @@ static int ft232r_speed(int divisor)
 
 	if (jtag_libusb_control_transfer(adapter,
 		LIBUSB_REQUEST_TYPE_VENDOR | LIBUSB_RECIPIENT_DEVICE | LIBUSB_ENDPOINT_OUT,
-		SIO_SET_BAUD_RATE, divisor, 0, 0, 0, 1000) != 0) {
+		SIO_SET_BAUD_RATE, divisor, 0, NULL, 0, 1000) != 0) {
 		LOG_ERROR("cannot set baud rate");
 		return ERROR_JTAG_DEVICE_ERROR;
 	}
@@ -266,7 +266,7 @@ static int ft232r_init(void)
 	/* Reset the device. */
 	if (jtag_libusb_control_transfer(adapter,
 		LIBUSB_REQUEST_TYPE_VENDOR | LIBUSB_RECIPIENT_DEVICE | LIBUSB_ENDPOINT_OUT,
-		SIO_RESET, 0, 0, 0, 0, 1000) != 0) {
+		SIO_RESET, 0, 0, NULL, 0, 1000) != 0) {
 		LOG_ERROR("unable to reset device");
 		return ERROR_JTAG_INIT_FAILED;
 	}
@@ -275,7 +275,7 @@ static int ft232r_init(void)
 	if (jtag_libusb_control_transfer(adapter,
 		LIBUSB_REQUEST_TYPE_VENDOR | LIBUSB_RECIPIENT_DEVICE | LIBUSB_ENDPOINT_OUT,
 		SIO_SET_BITMODE, (1<<tck_gpio) | (1<<tdi_gpio) | (1<<tms_gpio) | (1<<ntrst_gpio) | (1<<nsysrst_gpio) | 0x400,
-		0, 0, 0, 1000) != 0) {
+		0, NULL, 0, 1000) != 0) {
 		LOG_ERROR("cannot set sync bitbang mode");
 		return ERROR_JTAG_INIT_FAILED;
 	}
@@ -288,13 +288,13 @@ static int ft232r_init(void)
 	if (jtag_libusb_control_transfer(adapter,
 		LIBUSB_REQUEST_TYPE_VENDOR | LIBUSB_RECIPIENT_DEVICE | LIBUSB_ENDPOINT_OUT,
 		SIO_SET_BAUD_RATE, divisor,
-		0, 0, 0, 1000) != 0) {
+		0, NULL, 0, 1000) != 0) {
 		LOG_ERROR("cannot set baud rate");
 		return ERROR_JTAG_INIT_FAILED;
 	}
 	if (jtag_libusb_control_transfer(adapter,
 		LIBUSB_REQUEST_TYPE_VENDOR | LIBUSB_RECIPIENT_DEVICE | LIBUSB_ENDPOINT_OUT,
-		SIO_SET_LATENCY_TIMER, latency_timer, 0, 0, 0, 1000) != 0) {
+		SIO_SET_LATENCY_TIMER, latency_timer, 0, NULL, 0, 1000) != 0) {
 		LOG_ERROR("unable to set latency timer");
 		return ERROR_JTAG_INIT_FAILED;
 	}
@@ -315,7 +315,7 @@ static int ft232r_quit(void)
 		if (jtag_libusb_control_transfer(adapter,
 			LIBUSB_REQUEST_TYPE_VENDOR | LIBUSB_RECIPIENT_DEVICE | LIBUSB_ENDPOINT_OUT,
 			SIO_SET_BITMODE, ft232r_restore_bitmode,
-			0, 0, 0, 1000) != 0) {
+			0, NULL, 0, 1000) != 0) {
 			LOG_ERROR("cannot set bitmode to restore serial port");
 		}
 	}
diff --git a/src/jtag/drivers/ftdi.c b/src/jtag/drivers/ftdi.c
index 6356a49..85b4513 100644
--- a/src/jtag/drivers/ftdi.c
+++ b/src/jtag/drivers/ftdi.c
@@ -181,7 +181,7 @@ static int ftdi_set_signal(const struct signal *s, char value)
 		oe = s->invert_oe;
 		break;
 	default:
-		assert(0 && "invalid signal level specifier");
+		LOG_ERROR("invalid signal level specifier \'%c\'(0x%02x)", value, value);
 		return ERROR_FAIL;
 	}
 
diff --git a/src/jtag/drivers/mpsse.c b/src/jtag/drivers/mpsse.c
index 9f2fdde..fad91dd 100644
--- a/src/jtag/drivers/mpsse.c
+++ b/src/jtag/drivers/mpsse.c
@@ -313,7 +313,7 @@ struct mpsse_ctx *mpsse_open(const uint16_t vids[], const uint16_t pids[], const
 	int err;
 
 	if (!ctx)
-		return 0;
+		return NULL;
 
 	bit_copy_queue_init(&ctx->read_queue);
 	ctx->read_chunk_size = 16384;
@@ -348,7 +348,7 @@ struct mpsse_ctx *mpsse_open(const uint16_t vids[], const uint16_t pids[], const
 				description ? description : "*",
 				serial ? serial : "*",
 				location ? location : "*");
-		ctx->usb_dev = 0;
+		ctx->usb_dev = NULL;
 		goto error;
 	}
 
@@ -378,7 +378,7 @@ struct mpsse_ctx *mpsse_open(const uint16_t vids[], const uint16_t pids[], const
 	return ctx;
 error:
 	mpsse_close(ctx);
-	return 0;
+	return NULL;
 }
 
 void mpsse_close(struct mpsse_ctx *ctx)
@@ -465,13 +465,13 @@ static unsigned buffer_add_read(struct mpsse_ctx *ctx, uint8_t *in, unsigned in_
 void mpsse_clock_data_out(struct mpsse_ctx *ctx, const uint8_t *out, unsigned out_offset,
 	unsigned length, uint8_t mode)
 {
-	mpsse_clock_data(ctx, out, out_offset, 0, 0, length, mode);
+	mpsse_clock_data(ctx, out, out_offset, NULL, 0, length, mode);
 }
 
 void mpsse_clock_data_in(struct mpsse_ctx *ctx, uint8_t *in, unsigned in_offset, unsigned length,
 	uint8_t mode)
 {
-	mpsse_clock_data(ctx, 0, 0, in, in_offset, length, mode);
+	mpsse_clock_data(ctx, NULL, 0, in, in_offset, length, mode);
 }
 
 void mpsse_clock_data(struct mpsse_ctx *ctx, const uint8_t *out, unsigned out_offset, uint8_t *in,
@@ -548,7 +548,7 @@ void mpsse_clock_data(struct mpsse_ctx *ctx, const uint8_t *out, unsigned out_of
 void mpsse_clock_tms_cs_out(struct mpsse_ctx *ctx, const uint8_t *out, unsigned out_offset,
 	unsigned length, bool tdi, uint8_t mode)
 {
-	mpsse_clock_tms_cs(ctx, out, out_offset, 0, 0, length, tdi, mode);
+	mpsse_clock_tms_cs(ctx, out, out_offset, NULL, 0, length, tdi, mode);
 }
 
 void mpsse_clock_tms_cs(struct mpsse_ctx *ctx, const uint8_t *out, unsigned out_offset, uint8_t *in,
@@ -842,7 +842,7 @@ int mpsse_flush(struct mpsse_ctx *ctx)
 	if (ctx->write_count == 0)
 		return retval;
 
-	struct libusb_transfer *read_transfer = 0;
+	struct libusb_transfer *read_transfer = NULL;
 	struct transfer_result read_result = { .ctx = ctx, .done = true };
 	if (ctx->read_count) {
 		buffer_write_byte(ctx, 0x87); /* SEND_IMMEDIATE */
diff --git a/src/jtag/drivers/opendous.c b/src/jtag/drivers/opendous.c
index c353aef..ad980bf 100644
--- a/src/jtag/drivers/opendous.c
+++ b/src/jtag/drivers/opendous.c
@@ -347,7 +347,7 @@ static int opendous_init(void)
 
 	opendous_jtag_handle = opendous_usb_open();
 
-	if (opendous_jtag_handle == 0) {
+	if (!opendous_jtag_handle) {
 		LOG_ERROR("Cannot find opendous Interface! Please check connection and permissions.");
 		return ERROR_JTAG_INIT_FAILED;
 	}
diff --git a/src/jtag/drivers/parport.c b/src/jtag/drivers/parport.c
index 4073d06..d26a510 100644
--- a/src/jtag/drivers/parport.c
+++ b/src/jtag/drivers/parport.c
@@ -411,9 +411,13 @@ COMMAND_HANDLER(parport_handle_parport_cable_command)
 		return ERROR_OK;
 
 	/* only if the cable name wasn't overwritten by cmdline */
-	if (parport_cable == 0) {
+	if (!parport_cable) {
 		/* REVISIT first verify that it's listed in cables[] ... */
 		parport_cable = malloc(strlen(CMD_ARGV[0]) + sizeof(char));
+		if (!parport_cable) {
+			LOG_ERROR("Out of memory");
+			return ERROR_FAIL;
+		}
 		strcpy(parport_cable, CMD_ARGV[0]);
 	}
 
diff --git a/src/jtag/drivers/rlink.c b/src/jtag/drivers/rlink.c
index c933b3e..65f7494 100644
--- a/src/jtag/drivers/rlink.c
+++ b/src/jtag/drivers/rlink.c
@@ -632,7 +632,7 @@ static int dtc_queue_run(void)
 	uint8_t dtc_mask, tdo_mask;
 	uint8_t reply_buffer[USB_EP2IN_SIZE];
 
-	assert((dtc_queue.rq_head != 0) == (dtc_queue.reply_index > 0));
+	assert((!!dtc_queue.rq_head) == (dtc_queue.reply_index > 0));
 	assert(dtc_queue.cmd_index < USB_EP2BANK_SIZE);
 	assert(dtc_queue.reply_index <= USB_EP2IN_SIZE);
 
diff --git a/src/jtag/drivers/stlink_usb.c b/src/jtag/drivers/stlink_usb.c
index 5b051c1..ee62954 100644
--- a/src/jtag/drivers/stlink_usb.c
+++ b/src/jtag/drivers/stlink_usb.c
@@ -3694,7 +3694,7 @@ static int stlink_open(struct hl_interface_param_s *param, enum stlink_mode mode
 
 	h = calloc(1, sizeof(struct stlink_usb_handle_s));
 
-	if (h == 0) {
+	if (!h) {
 		LOG_DEBUG("malloc failed");
 		return ERROR_FAIL;
 	}
diff --git a/src/jtag/drivers/sysfsgpio.c b/src/jtag/drivers/sysfsgpio.c
index ee254d6..a5f5fd3 100644
--- a/src/jtag/drivers/sysfsgpio.c
+++ b/src/jtag/drivers/sysfsgpio.c
@@ -571,7 +571,7 @@ static struct bitbang_interface sysfsgpio_bitbang = {
 	.swdio_read = sysfsgpio_swdio_read,
 	.swdio_drive = sysfsgpio_swdio_drive,
 	.swd_write = sysfsgpio_swd_write,
-	.blink = 0
+	.blink = NULL,
 };
 
 /* helper func to close and cleanup files only if they were valid/ used */
diff --git a/src/jtag/drivers/ti_icdi_usb.c b/src/jtag/drivers/ti_icdi_usb.c
index ca52559..3e36218 100644
--- a/src/jtag/drivers/ti_icdi_usb.c
+++ b/src/jtag/drivers/ti_icdi_usb.c
@@ -369,7 +369,7 @@ static int icdi_usb_query(void *handle)
 	if (h->max_packet != ICDI_PACKET_SIZE) {
 		h->read_buffer = realloc(h->read_buffer, h->max_packet);
 		h->write_buffer = realloc(h->write_buffer, h->max_packet);
-		if (h->read_buffer == 0 || h->write_buffer == 0) {
+		if (!h->read_buffer || !h->write_buffer) {
 			LOG_ERROR("unable to reallocate memory");
 			return ERROR_FAIL;
 		}
@@ -664,7 +664,7 @@ static int icdi_usb_open(struct hl_interface_param_s *param, void **fd)
 
 	h = calloc(1, sizeof(struct icdi_usb_handle_s));
 
-	if (h == 0) {
+	if (!h) {
 		LOG_ERROR("unable to allocate memory");
 		return ERROR_FAIL;
 	}
@@ -712,7 +712,7 @@ static int icdi_usb_open(struct hl_interface_param_s *param, void **fd)
 	h->write_buffer = malloc(ICDI_PACKET_SIZE);
 	h->max_packet = ICDI_PACKET_SIZE;
 
-	if (h->read_buffer == 0 || h->write_buffer == 0) {
+	if (!h->read_buffer || !h->write_buffer) {
 		LOG_DEBUG("malloc failed");
 		goto error_open;
 	}
diff --git a/src/jtag/drivers/usbprog.c b/src/jtag/drivers/usbprog.c
index 0c0f24e..5d41656 100644
--- a/src/jtag/drivers/usbprog.c
+++ b/src/jtag/drivers/usbprog.c
@@ -148,7 +148,7 @@ static int usbprog_init(void)
 	usbprog_jtag_handle = usbprog_jtag_open();
 
 	tms_chain_index = 0;
-	if (usbprog_jtag_handle == 0) {
+	if (!usbprog_jtag_handle) {
 		LOG_ERROR("Can't find USB JTAG Interface! Please check connection and permissions.");
 		return ERROR_JTAG_INIT_FAILED;
 	}
diff --git a/src/jtag/drivers/xds110.c b/src/jtag/drivers/xds110.c
index 8e5d638..3ea98ad 100644
--- a/src/jtag/drivers/xds110.c
+++ b/src/jtag/drivers/xds110.c
@@ -1300,7 +1300,7 @@ static int xds110_swd_run_queue(void)
 
 	/* Transfer results into caller's buffers */
 	for (result = 0; result < xds110.txn_result_count; result++)
-		if (xds110.txn_dap_results[result] != 0)
+		if (xds110.txn_dap_results[result])
 			*xds110.txn_dap_results[result] = dap_results[result];
 
 	xds110.txn_request_size = 0;
@@ -1611,7 +1611,7 @@ static void xds110_flush(void)
 			}
 			bits = 0;
 		}
-		if (xds110.txn_scan_results[result].buffer != 0)
+		if (xds110.txn_scan_results[result].buffer)
 			bit_copy(xds110.txn_scan_results[result].buffer, 0, data_pntr,
 				bits, xds110.txn_scan_results[result].num_bits);
 		bits += xds110.txn_scan_results[result].num_bits;
@@ -1687,8 +1687,8 @@ static void xds110_execute_pathmove(struct jtag_command *cmd)
 	if (num_states == 0)
 		return;
 
-	path = (uint8_t *)malloc(num_states * sizeof(uint8_t));
-	if (path == 0) {
+	path = malloc(num_states * sizeof(uint8_t));
+	if (path) {
 		LOG_ERROR("XDS110: unable to allocate memory");
 		return;
 	}
@@ -1766,7 +1766,7 @@ static void xds110_queue_scan(struct jtag_command *cmd)
 	/* Clear data out buffer to default value of all zeros */
 	memset((void *)buffer, 0x00, total_bytes);
 	for (i = 0; i < cmd->cmd.scan->num_fields; i++) {
-		if (cmd->cmd.scan->fields[i].out_value != 0) {
+		if (cmd->cmd.scan->fields[i].out_value) {
 			/* Copy over data to scan out into request buffer */
 			bit_copy(buffer, offset, cmd->cmd.scan->fields[i].out_value, 0,
 				cmd->cmd.scan->fields[i].num_bits);