X-Git-Url: http://git.ozlabs.org/?p=petitboot;a=blobdiff_plain;f=discover%2Fgrub2%2Fbuiltins.c;h=8bff7328108479f1b95dbd2d3196cdeada238808;hp=4261eebdbdea73563b4c6d50d01a975e8fea11e3;hb=03eba1d68dbf7ffc9690d73f957c33b8f492e627;hpb=27037bcd151ff8ecad1aaca7eaa06fb5c3f9fd1f;ds=sidebyside

diff --git a/discover/grub2/builtins.c b/discover/grub2/builtins.c
index 4261eeb..8bff732 100644
--- a/discover/grub2/builtins.c
+++ b/discover/grub2/builtins.c
@@ -5,8 +5,9 @@
 #include <log/log.h>
 #include <types/types.h>
 #include <talloc/talloc.h>
-#include <array-size/array-size.h>
+#include <util/util.h>
 
+#include "discover/parser.h"
 #include "grub2.h"
 
 
@@ -123,6 +124,190 @@ static int builtin_search(struct grub2_script *script,
 	return 0;
 }
 
+/* Note that GRUB does not follow symlinks in evaluating all file
+ * tests but -s, unlike below. However, it seems like a bad idea to
+ * emulate GRUB's behavior (e.g., it would take extra work), so we
+ * implement the behavior that coreutils' test binary has. */
+static bool builtin_test_op_file(struct grub2_script *script, char op,
+		const char *file)
+{
+	bool result;
+	int rc;
+	struct stat statbuf;
+
+	rc = parser_stat_path(script->ctx, script->ctx->device,
+			file, &statbuf);
+	if (rc)
+		return false;
+
+	switch (op) {
+	case 's':
+		/* -s: return true if file exists and has non-zero size */
+		result = statbuf.st_size > 0;
+		break;
+	case 'f':
+		/* -f: return true if file exists and is not a directory. This is
+		 * different than the behavior of "test", but is what GRUB does
+		 * (though note as above that we follow symlinks unlike GRUB). */
+		result = !S_ISDIR(statbuf.st_mode);
+		break;
+	default:
+		result = false;
+
+	}
+
+	return result;
+}
+
+/* See comment at builtin_test_op_file for differences between how
+ * GRUB implements file tests versus Petitboot's GRUB parser. */
+static bool builtin_test_op_dir(struct grub2_script *script, char op,
+		const char *dir)
+{
+	int rc;
+	struct stat statbuf;
+
+	if (op != 'd')
+		return false;
+
+	rc = parser_stat_path(script->ctx, script->ctx->device, dir, &statbuf);
+	if (rc) {
+		return false;
+	}
+
+	return S_ISDIR(statbuf.st_mode);
+}
+
+static bool builtin_test_op(struct grub2_script *script,
+		int argc, char **argv, int *consumed)
+{
+	char *op;
+
+	if (argc >= 3) {
+		const char *a1, *a2;
+
+		a1 = argv[0];
+		op = argv[1];
+		a2 = argv[2];
+
+		if (!strcmp(op, "=") || !strcmp(op, "==")) {
+			*consumed = 3;
+			return !strcmp(a1, a2);
+		}
+
+		if (!strcmp(op, "!=")) {
+			*consumed = 3;
+			return strcmp(a1, a2);
+		}
+
+		if (!strcmp(op, "<")) {
+			*consumed = 3;
+			return strcmp(a1, a2) < 0;
+		}
+
+		if (!strcmp(op, ">")) {
+			*consumed = 3;
+			return strcmp(a1, a2) > 0;
+		}
+	}
+
+	if (argc >= 2) {
+		const char *a1;
+
+		op = argv[0];
+		a1 = argv[1];
+
+		if (!strcmp(op, "-z")) {
+			*consumed = 2;
+			return strlen(a1) == 0;
+		}
+
+		if (!strcmp(op, "-n")) {
+			*consumed = 2;
+			return strlen(a1) != 0;
+		}
+
+		if (!strcmp(op, "-s") || !strcmp(op, "-f")) {
+			*consumed = 2;
+			return builtin_test_op_file(script, op[1], a1);
+		}
+
+		if (!strcmp(op, "-d")) {
+			*consumed = 2;
+			return builtin_test_op_dir(script, op[1], a1);
+		}
+	}
+
+	op = argv[0];
+	*consumed = 1;
+	return strlen(op) > 0;
+}
+
+static int builtin_test(struct grub2_script *script,
+		void *data __attribute__((unused)),
+		int argc, char *argv[])
+{
+	int consumed;
+	bool not, rc;
+
+	if (!strcmp(argv[0], "[") && !strcmp(argv[argc - 1], "]"))
+		argc--;
+
+	/* skip command name */
+	argc--;
+	argv++;
+
+	not = false;
+	rc = false;
+
+	for (consumed = 0; argc > 0; argv += consumed, argc -= consumed) {
+
+		if (!strcmp(argv[0], "!")) {
+			not = true;
+			consumed = 1;
+			continue;
+		}
+
+		if (!strcmp(argv[0], "-a")) {
+			if (!rc)
+				return 1;
+			consumed = 1;
+			continue;
+		}
+
+		if (!strcmp(argv[0], "-o")) {
+			if (rc)
+				return 0;
+			consumed = 1;
+			continue;
+		}
+
+		rc = builtin_test_op(script, argc, argv, &consumed);
+		if (not) {
+			rc = !rc;
+			not = false;
+		}
+	}
+
+	return rc ? 0 : 1;
+}
+
+static int builtin_true(struct grub2_script *script __attribute__((unused)),
+		void *data __attribute__((unused)),
+		int argc __attribute__((unused)),
+		char *argv[] __attribute__((unused)))
+{
+	return 0;
+}
+
+static int builtin_false(struct grub2_script *script __attribute__((unused)),
+		void *data __attribute__((unused)),
+		int argc __attribute__((unused)),
+		char *argv[] __attribute__((unused)))
+{
+	return 1;
+}
+
 static int builtin_nop(struct grub2_script *script __attribute__((unused)),
 		void *data __attribute__((unused)),
 		int argc __attribute__((unused)),
@@ -131,6 +316,14 @@ 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[]);
+int builtin_save_env(struct grub2_script *script,
+		void *data __attribute__((unused)),
+		int argc, char *argv[]);
+
+
 static struct {
 	const char *name;
 	grub2_function fn;
@@ -143,6 +336,10 @@ static struct {
 		.name = "linux",
 		.fn = builtin_linux,
 	},
+	{
+		.name = "linux16",
+		.fn = builtin_linux,
+	},
 	{
 		.name = "initrd",
 		.fn = builtin_initrd,
@@ -150,7 +347,31 @@ static struct {
 	{
 		.name = "search",
 		.fn = builtin_search,
-	}
+	},
+	{
+		.name = "[",
+		.fn = builtin_test,
+	},
+	{
+		.name = "test",
+		.fn = builtin_test,
+	},
+	{
+		.name = "true",
+		.fn = builtin_true,
+	},
+	{
+		.name = "false",
+		.fn = builtin_false,
+	},
+	{
+		.name = "load_env",
+		.fn = builtin_load_env,
+	},
+	{
+		.name = "save_env",
+		.fn = builtin_save_env,
+	},
 };
 
 static const char *nops[] = {