discover: Add debug flag to config

This change adds a debug flag to the config, and groups it under
not-user-modifiable parts of struct config.

This means we no longer need the pb-sysinfo helper, as the last
remaining function (--debug-enabled) can be implemented with pb-config.

Signed-off-by: Jeremy Kerr <jk@ozlabs.org>

1 files changed, 27 insertions, 0 deletions

diff --git a/discover/platform.c b/discover/platform.c
index 65e9ed4..418b9ea 100644
--- a/discover/platform.c
+++ b/discover/platform.c
@@ -1,7 +1,11 @@
 
+#define _GNU_SOURCE
+
+#include <fcntl.h>
 #include <string.h>
 
 #include <log/log.h>
+#include <file/file.h>
 #include <types/types.h>
 #include <talloc/talloc.h>
 
@@ -11,6 +15,8 @@ void			*platform_ctx;
 static struct platform	*platform;
 static struct config	*config;
 
+static const char *kernel_cmdline_debug = "petitboot.debug";
+
 static const char *device_type_name(enum device_type type)
 {
 	switch (type) {
@@ -85,6 +91,25 @@ static void dump_config(struct config *config)
 	pb_log(" language: %s\n", config->lang ?: "");
 }
 
+static bool config_debug_on_cmdline(void)
+{
+	char buf[600];
+	int rc, fd;
+
+	fd = open("/proc/cmdline", O_RDONLY);
+	if (fd < 0)
+		return false;
+
+	rc = read(fd, buf, sizeof(buf));
+	close(fd);
+
+	if (rc <= 0)
+		return false;
+
+	return memmem(buf, rc, kernel_cmdline_debug,
+			strlen(kernel_cmdline_debug)) != NULL;
+}
+
 void config_set_defaults(struct config *config)
 {
 	config->autoboot_enabled = true;
@@ -105,6 +130,8 @@ void config_set_defaults(struct config *config)
 	config->boot_priorities[0].priority = 2;
 	config->boot_priorities[1].type = DEVICE_TYPE_DISK;
 	config->boot_priorities[1].priority = 1;
+
+	config->debug = config_debug_on_cmdline();
 }
 
 int platform_init(void *ctx)