X-Git-Url: https://git.ao2.it/libam7xxx.git/blobdiff_plain/a27837d8dd8b78b4fcc9224d83d2f85fdf8eb19f..d2b3bd440d4700abf2e6b503d3a864af1496026e:/src/am7xxx.c

diff --git a/src/am7xxx.c b/src/am7xxx.c
index 11c259d..4cfc9a9 100644
--- a/src/am7xxx.c
+++ b/src/am7xxx.c
@@ -19,6 +19,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
+#include <stdarg.h>
 #include <errno.h>
 #include <libusb.h>
 
@@ -27,6 +28,27 @@
 
 #define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
 
+/* If we're not using GNU C, elide __attribute__
+ * taken from: http://unixwiz.net/techtips/gnu-c-attributes.html)
+ */
+#ifndef __GNUC__
+#  define  __attribute__(x)  /*NOTHING*/
+#endif
+
+static void log_message(am7xxx_context *ctx,
+			int level,
+			const char *function,
+			int line,
+			const char *fmt,
+			...) __attribute__ ((format (printf, 5, 6)));
+
+#define fatal(...)        log_message(NULL, AM7XXX_LOG_FATAL,   __func__, __LINE__, __VA_ARGS__)
+#define error(ctx, ...)   log_message(ctx,  AM7XXX_LOG_ERROR,   __func__, __LINE__, __VA_ARGS__)
+#define warning(ctx, ...) log_message(ctx,  AM7XXX_LOG_WARNING, __func__, 0,        __VA_ARGS__)
+#define info(ctx, ...)    log_message(ctx,  AM7XXX_LOG_INFO,    __func__, 0,        __VA_ARGS__)
+#define debug(ctx, ...)   log_message(ctx,  AM7XXX_LOG_DEBUG,   __func__, 0,        __VA_ARGS__)
+#define trace(ctx, ...)   log_message(ctx,  AM7XXX_LOG_TRACE,   NULL,     0,        __VA_ARGS__)
+
 struct am7xxx_usb_device_descriptor {
 	const char *name;
 	uint16_t vendor_id;
@@ -55,11 +77,13 @@ static struct am7xxx_usb_device_descriptor supported_devices[] = {
 struct _am7xxx_device {
 	libusb_device_handle *usb_device;
 	uint8_t buffer[AM7XXX_HEADER_WIRE_SIZE];
+	am7xxx_context *ctx;
 	am7xxx_device *next;
 };
 
 struct _am7xxx_context {
 	libusb_context *usb_context;
+	int log_level;
 	am7xxx_device *devices_list;
 };
 
@@ -321,10 +345,47 @@ static int send_header(am7xxx_device *dev, struct am7xxx_header *h)
 	return ret;
 }
 
-static am7xxx_device *add_new_device(am7xxx_device **devices_list)
+/* When level == AM7XXX_LOG_FATAL do not check the log_level from the context
+ * and print the message unconditionally, this makes it possible to print
+ * fatal messages even early on initialization, before the context has been
+ * set up */
+static void log_message(am7xxx_context *ctx,
+			int level,
+			const char *function,
+			int line,
+			const char *fmt,
+			...)
 {
+	va_list ap;
+
+	if (level == AM7XXX_LOG_FATAL || (ctx && level <= ctx->log_level)) {
+		if (function) {
+			fprintf(stderr, "%s", function);
+			if (line)
+				fprintf(stderr, "[%d]", line);
+			fprintf(stderr, ": ");
+		}
+
+		va_start(ap, fmt);
+		vfprintf(stderr, fmt, ap);
+		va_end(ap);
+	}
+
+	return;
+}
+
+static am7xxx_device *add_new_device(am7xxx_context *ctx)
+{
+	am7xxx_device **devices_list;
 	am7xxx_device *new_device;
 
+	if (ctx == NULL) {
+		fprintf(stderr, "%s: context must not be NULL!\n", __func__);
+		return NULL;
+	}
+
+	devices_list = &(ctx->devices_list);
+
 	new_device = malloc(sizeof(*new_device));
 	if (new_device == NULL) {
 		perror("malloc");
@@ -332,6 +393,8 @@ static am7xxx_device *add_new_device(am7xxx_device **devices_list)
 	}
 	memset(new_device, 0, sizeof(*new_device));
 
+	new_device->ctx = ctx;
+
 	if (*devices_list == NULL) {
 		*devices_list = new_device;
 	} else {
@@ -343,12 +406,18 @@ static am7xxx_device *add_new_device(am7xxx_device **devices_list)
 	return new_device;
 }
 
-static am7xxx_device *find_device(am7xxx_device *devices_list,
+static am7xxx_device *find_device(am7xxx_context *ctx,
 				  unsigned int device_index)
 {
 	unsigned int i = 0;
-	am7xxx_device *current = devices_list;
+	am7xxx_device *current;
 
+	if (ctx == NULL) {
+		fprintf(stderr, "%s: context must not be NULL!\n", __func__);
+		return NULL;
+	}
+
+	current = ctx->devices_list;
 	while (current && i++ < device_index)
 		current = current->next;
 
@@ -420,7 +489,7 @@ static int scan_devices(am7xxx_context *ctx, scan_op op,
 					printf("am7xxx device found, index: %d, name: %s\n",
 					       current_index,
 					       supported_devices[j].name);
-					new_device = add_new_device(&(ctx->devices_list));
+					new_device = add_new_device(ctx);
 					if (new_device == NULL) {
 						/* XXX, the caller may want
 						 * to call am7xxx_shutdown() if
@@ -433,7 +502,7 @@ static int scan_devices(am7xxx_context *ctx, scan_op op,
 				} else if (op == SCAN_OP_OPEN_DEVICE &&
 					   current_index == open_device_index) {
 
-					*dev = find_device(ctx->devices_list, open_device_index);
+					*dev = find_device(ctx, open_device_index);
 					if (*dev == NULL) {
 						ret = -ENODEV;
 						goto out;
@@ -483,6 +552,9 @@ int am7xxx_init(am7xxx_context **ctx)
 	}
 	memset(*ctx, 0, sizeof(**ctx));
 
+	/* Set the highest log level during initialization */
+	(*ctx)->log_level = AM7XXX_LOG_TRACE;
+
 	ret = libusb_init(&((*ctx)->usb_context));
 	if (ret < 0)
 		goto out_free_context;
@@ -496,6 +568,8 @@ int am7xxx_init(am7xxx_context **ctx)
 		goto out;
 	}
 
+	/* Set a quieter log level as default for normal operation */
+	(*ctx)->log_level = AM7XXX_LOG_ERROR;
 	return 0;
 
 out_free_context:
@@ -527,6 +601,11 @@ void am7xxx_shutdown(am7xxx_context *ctx)
 	ctx = NULL;
 }
 
+void am7xxx_set_log_level(am7xxx_context *ctx, am7xxx_log_level log_level)
+{
+	ctx->log_level = log_level;
+}
+
 int am7xxx_open_device(am7xxx_context *ctx, am7xxx_device **dev,
 		       unsigned int device_index)
 {