From: Jeremy Kerr <jk@ozlabs.org>
Date: Fri, 27 Sep 2013 06:21:53 +0000 (+0800)
Subject: discover/grub2: Implement load_env
X-Git-Tag: v1.0.0~402
X-Git-Url: https://git.ozlabs.org/?p=petitboot;a=commitdiff_plain;h=fcbb46482c413192756ce865a7336c5638fda6d3

discover/grub2: Implement load_env

Use the new parser_request_file API to access the GRUB environment
block.

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

diff --git a/discover/grub2/Makefile.am b/discover/grub2/Makefile.am
index 71f3282..902f94f 100644
--- a/discover/grub2/Makefile.am
+++ b/discover/grub2/Makefile.am
@@ -30,6 +30,7 @@ grub2-parser.ro$(EXEEXT): $(grub2_parser_ro_OBJECTS)
 
 grub2_parser_ro_SOURCES = \
 	builtins.c \
+	env.c \
 	grub2.h \
 	grub2.c \
 	lexer.l \
diff --git a/discover/grub2/builtins.c b/discover/grub2/builtins.c
index 7a5d867..71ae61a 100644
--- a/discover/grub2/builtins.c
+++ b/discover/grub2/builtins.c
@@ -256,6 +256,10 @@ static int builtin_nop(struct grub2_script *script __attribute__((unused)),
 	return 0;
 }
 
+extern int builtin_load_env(struct grub2_script *script,
+		void *data __attribute__((unused)),
+		int argc, char *argv[]);
+
 static struct {
 	const char *name;
 	grub2_function fn;
@@ -296,6 +300,10 @@ static struct {
 		.name = "false",
 		.fn = builtin_false,
 	},
+	{
+		.name = "load_env",
+		.fn = builtin_load_env,
+	},
 };
 
 static const char *nops[] = {
diff --git a/discover/grub2/env.c b/discover/grub2/env.c
new file mode 100644
index 0000000..e28c9fe
--- /dev/null
+++ b/discover/grub2/env.c
@@ -0,0 +1,107 @@
+
+#include <stdio.h>
+#include <string.h>
+
+#include <log/log.h>
+#include <types/types.h>
+#include <talloc/talloc.h>
+#include <array-size/array-size.h>
+
+#include <discover/parser.h>
+#include <discover/file.h>
+
+#include "grub2.h"
+
+static const char *default_envfile = "grubenv";
+static const char *signature = "# GRUB Environment Block\n";
+
+static int parse_buf_to_env(struct grub2_script *script, void *buf, int len)
+{
+	char *tmp, *line, *sep;
+	int siglen;
+
+	siglen = strlen(signature);
+
+	if (len < siglen) {
+		pb_log("grub environment block too small\n");
+		return -1;
+	}
+
+	if (memcmp(buf, signature, siglen)) {
+		pb_log("grub environment block has invalid signature\n");
+		return -1;
+	}
+
+	buf += siglen;
+
+	for (line = strtok_r(buf, "\n", &tmp); line;
+				line = strtok_r(NULL, "\n", &tmp)) {
+
+		if (*line == '#')
+			continue;
+
+		sep = strchr(line, '=');
+		if (!sep)
+			continue;
+		if (sep == line)
+			continue;
+
+		*sep = '\0';
+		script_env_set(script, line, sep + 1);
+	}
+
+	return 0;
+}
+
+int builtin_load_env(struct grub2_script *script,
+		void *data __attribute__((unused)),
+		int argc, char *argv[]);
+
+int builtin_load_env(struct grub2_script *script,
+		void *data __attribute__((unused)),
+		int argc, char *argv[])
+{
+	struct discover_device *dev = script->ctx->device;
+	const char *envfile;
+	char *buf, *envpath;
+	int rc, len;
+
+	/* we only support local filesystems */
+	if (!dev->mounted) {
+		pb_log("load_env: can't load from a non-mounted device (%s)\n",
+				dev->device->id);
+		return -1;
+	}
+
+	if (argc == 3 && !strcmp(argv[1], "-f"))
+		envfile = argv[2];
+	else
+		envfile = default_envfile;
+
+	envpath = talloc_asprintf(script, "%s/%s",
+				script_env_get(script, "prefix") ? : "",
+				envfile);
+
+	rc = parser_request_file(script->ctx, dev, envpath, &buf, &len);
+
+	if (!rc)
+		rc = parse_buf_to_env(script, buf, len);
+
+	talloc_free(buf);
+
+	return 0;
+}
+
+int builtin_save_env(struct grub2_script *script,
+		void *data __attribute__((unused)),
+		int argc, char *argv[]);
+
+int builtin_save_env(struct grub2_script *script __attribute__((unused)),
+		void *data __attribute__((unused)),
+		int argc __attribute__((unused)),
+		char *argv[] __attribute__((unused)))
+{
+	/* todo: save */
+	return 0;
+}
+
diff --git a/test/parser/Makefile.am b/test/parser/Makefile.am
index e7146c5..165b9ae 100644
--- a/test/parser/Makefile.am
+++ b/test/parser/Makefile.am
@@ -33,6 +33,7 @@ TESTS = \
 	test-grub2-default-multiword \
 	test-grub2-multiple-resolve \
 	test-grub2-single-line-if \
+	test-grub2-load-env \
 	test-grub2-f18-ppc64 \
 	test-grub2-ubuntu-13_04-x86 \
 	test-grub2-lexer-error \
diff --git a/test/parser/test-grub2-load-env.c b/test/parser/test-grub2-load-env.c
new file mode 100644
index 0000000..2f4e96e
--- /dev/null
+++ b/test/parser/test-grub2-load-env.c
@@ -0,0 +1,32 @@
+
+#include "parser-test.h"
+
+#if 0 /* PARSER_EMBEDDED_CONFIG */
+load_env
+menuentry 'Linux' {
+	linux   $kernel
+}
+#endif
+
+void run_test(struct parser_test *test)
+{
+	struct discover_boot_option *opt;
+	struct discover_context *ctx;
+
+	test_add_file_string(test, test->ctx->device,
+				"/boot/grub/grubenv",
+				"# GRUB Environment Block\n"
+				"kernel=vmlinux-from-env\n");
+
+	test_read_conf_embedded(test);
+	test_run_parser(test, "grub2");
+
+	ctx = test->ctx;
+
+	check_boot_option_count(ctx, 1);
+	opt = get_boot_option(ctx, 0);
+
+	check_name(opt, "Linux");
+	check_resolved_local_resource(opt->boot_image, ctx->device,
+			"/vmlinux-from-env");
+}