Split common routines from kboot parser

Pull out the common .conf file parsing logic from kboot-parser.c and
into two new files parser-conf.h and parser-conf.c, and rework
the kboot parser to use those common routines.

The new common routines are based on a .conf file parser context
struct conf_context.  The specific parsers setup the context then
call the main parsing entry routine conf_parse().  conf_parse()
uses the context info to open and read .conf files and call
parser specific callbacks to process name:value pairs and to
add boot_option instances to the discover server.

Signed-off-by: Geoff Levand <geoffrey.levand@am.sony.com>
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>

1 files changed, 99 insertions, 269 deletions

diff --git a/discover/kboot-parser.c b/discover/kboot-parser.c
index f2fac3e..e688c22 100644
--- a/discover/kboot-parser.c
+++ b/discover/kboot-parser.c
@@ -1,319 +1,149 @@
 #define _GNU_SOURCE
 
-#include <errno.h>
+#include <assert.h>
 #include <stdlib.h>
-#include <stdio.h>
 #include <string.h>
-#include <ctype.h>
-#include <unistd.h>
-
-#include <fcntl.h>
-#include <sys/types.h>
-#include <sys/stat.h>
-
-#include <talloc/talloc.h>
-#include <log/log.h>
 
+#include "log/log.h"
+#include "talloc/talloc.h"
 #include "pb-protocol/pb-protocol.h"
-#include "paths.h"
-#include "params.h"
+#include "parser-conf.h"
 #include "parser-utils.h"
-#include "device-handler.h"
-
-#define buf_size 1024
-
-struct kboot_context {
-	struct discover_context *discover;
-
-	char *buf;
-
-	struct global_option {
-		char *name;
-		char *value;
-	} *global_options;
-	int n_global_options;
-};
-
-static int param_is_ignored(const char *param)
-{
-	static const char *ignored_options[] =
-		{ "message", "timeout", "default", NULL };
-	const char **str;
-
-	for (str = ignored_options; *str; str++)
-		if (streq(*str, param))
-			return 1;
-	return 0;
-}
-
-/**
- * Splits a name=value pair, with value terminated by @term (or nul). if there
- * is no '=', then only the value is populated, and *name is set to NULL. The
- * string is modified in place.
- *
- * Returns the next byte to process, or null if we've hit the end of the
- * string.
- *
- * */
-static char *get_param_pair(char *str, char **name_out, char **value_out,
-		char terminator)
-{
-	char *sep, *tmp, *name, *value;
-
-	/* terminate the value */
-	tmp = strchr(str, terminator);
-	if (tmp)
-		*tmp = 0;
-	else
-		tmp = NULL;
-
-	sep = strchr(str, '=');
-	if (!sep) {
-		*name_out = NULL;
-		*value_out = str;
-		return tmp ? tmp + 1 : NULL;
-	}
-
-	/* terminate the name */
-	*sep = 0;
-
-	/* remove leading spaces */
-	for (name = str; isspace(*name); name++);
-	for (value = sep + 1; isspace(*value); value++);
-
-	/* .. and trailing ones.. */
-	for (sep--; isspace(*sep); sep--)
-		*sep = 0;
-	for (sep = value + strlen(value) - 1; isspace(*sep); sep--)
-		*sep = 0;
-
-	*name_out = name;
-	*value_out = value;
-
-	return tmp ? tmp + 1 : NULL;
-}
-
-static struct global_option global_options[] = {
-	{ .name = "root" },
-	{ .name = "initrd" },
-	{ .name = "video" },
-	{ .name = NULL }
-};
-
-/*
- * Check if an option (name=value) is a global option. If so, store it in
- * the global options table, and return 1. Otherwise, return 0.
- */
-static int check_for_global_option(struct kboot_context *ctx,
-		const char *name, const char *value)
-{
-	int i;
-
-	for (i = 0; i < ctx->n_global_options; i++) {
-		if (!strcmp(name, ctx->global_options[i].name)) {
-			global_options[i].value = strdup(value);
-			break;
-		}
-	}
-	return 0;
-}
+#include "paths.h"
 
-static char *get_global_option(
-		struct kboot_context *ctx __attribute__((unused)),
-		const char *name)
+static void kboot_process_pair(struct conf_context *conf, const char *name,
+		char *value)
 {
-	int i;
+	const char *const *ignored_names = conf->parser_info;
+	char *pos;
+	char *args;
+	const char *initrd;
+	const char *root;
+	struct boot_option *opt;
 
-	for (i = 0; global_options[i].name ;i++)
-		if (!strcmp(name, global_options[i].name))
-			return global_options[i].value;
+	if (conf_param_in_list(ignored_names, name))
+		return;
 
-	return NULL;
-}
-
-static int parse_option(struct kboot_context *kboot_ctx, char *opt_name,
-		char *config)
-{
-	char *pos, *name, *value, *root, *initrd, *cmdline, *tmp;
-	struct boot_option *opt;
+	if (conf_set_global_option(conf, name, value))
+		return;
 
-	root = initrd = cmdline = NULL;
+	/* opt must be associated with dc */
 
-	/* remove quotes around the value */
-	while (*config == '"' || *config == '\'')
-		config++;
+	opt = talloc_zero(conf->dc->device, struct boot_option);
 
-	pos = config + strlen(config) - 1;
-	while (*pos == '"' || *pos == '\'')
-		*(pos--) = 0;
+	if (!opt)
+		return;
 
-	if (!strlen(pos))
-		return 0;
+	opt->id = talloc_asprintf(opt, "%s#%s", conf->dc->device->id, name);
+	opt->name = talloc_strdup(opt, name);
 
-	pos = strchr(config, ' ');
+	args = talloc_strdup(opt, "");
+	initrd = conf_get_global_option(conf, "initrd");
+	root = conf_get_global_option(conf, "root");
 
-	opt = talloc_zero(kboot_ctx, struct boot_option);
-	opt->id = talloc_asprintf(opt, "%s#%s",
-			kboot_ctx->discover->device->id, opt_name);
-	opt->name = talloc_strdup(opt, opt_name);
+	pos = strchr(value, ' ');
 
 	/* if there's no space, it's only a kernel image with no params */
-	if (!pos) {
-		opt->boot_image_file = resolve_path(opt, config,
-				kboot_ctx->discover->device_path);
-		opt->description = talloc_strdup(opt, config);
-		goto out_add;
-	}
 
+	if (!pos)
+		goto out_add;
 	*pos = 0;
-	opt->boot_image_file = resolve_path(opt, config,
-			kboot_ctx->discover->device_path);
-
-	cmdline = talloc_array(opt, char, buf_size);
-	*cmdline = 0;
 
 	for (pos++; pos;) {
-		pos = get_param_pair(pos, &name, &value, ' ');
+		char *cl_name, *cl_value;
 
-		if (!name) {
-			strcat(cmdline, " ");
-			strcat(cmdline, value);
+		pos = conf_get_param_pair(pos, &cl_name, &cl_value, ' ');
 
-		} else if (streq(name, "initrd")) {
-			initrd = value;
-
-		} else if (streq(name, "root")) {
-			root = value;
-
-		} else {
-			strcat(cmdline, " ");
-			*(value - 1) = '=';
-			strcat(cmdline, name);
+		if (!cl_name) {
+			args = talloc_asprintf_append(args, "%s ", cl_value);
+			continue;
 		}
-	}
-
-	if (!root)
-		root = get_global_option(kboot_ctx, "root");
-	if (!initrd)
-		initrd = get_global_option(kboot_ctx, "initrd");
 
-	if (initrd) {
-		tmp = talloc_asprintf(opt, "initrd=%s %s", initrd, cmdline);
-		talloc_free(cmdline);
-		cmdline = tmp;
+		if (streq(cl_name, "initrd")) {
+			initrd = cl_value;
+			continue;
+		}
 
-		opt->initrd_file = resolve_path(opt, initrd,
-				kboot_ctx->discover->device_path);
-	}
+		if (streq(cl_name, "root")) {
+			root = cl_value;
+			continue;
+		}
 
-	if (root) {
-		tmp = talloc_asprintf(opt, "root=%s %s", root, cmdline);
-		talloc_free(cmdline);
-		cmdline = tmp;
-
-	} else if (initrd) {
-		/* if there's an initrd but no root, fake up /dev/ram0 */
-		tmp = talloc_asprintf(opt, "root=/dev/ram0 %s", cmdline);
-		talloc_free(cmdline);
-		cmdline = tmp;
+		args = talloc_asprintf_append(args, "%s=%s ", cl_name,
+			cl_value);
 	}
 
-	opt->boot_args = cmdline;
-
-	opt->description = talloc_asprintf(opt, "%s %s",
-			config, opt->boot_args);
-
 out_add:
-	device_add_boot_option(kboot_ctx->discover->device, opt);
-	return 1;
-}
+	opt->boot_image_file = resolve_path(opt, value, conf->dc->device_path);
 
-static void parse_buf(struct kboot_context *kboot_ctx)
-{
-	char *pos, *name, *value;
-
-	for (pos = kboot_ctx->buf; pos;) {
-		pos = get_param_pair(pos, &name, &value, '\n');
+	if (root) {
+		opt->boot_args = talloc_asprintf(opt, "root=%s %s", root, args);
+		talloc_free(args);
+	} else
+		opt->boot_args = args;
 
-		if (name == NULL || param_is_ignored(name))
-			continue;
+	if (initrd) {
+		opt->initrd_file = resolve_path(opt, initrd,
+				conf->dc->device_path);
 
-		if (*name == '#')
-			continue;
+		opt->description = talloc_asprintf(opt, "%s initrd=%s %s",
+			value, initrd, opt->boot_args);
+	} else
+		opt->description = talloc_asprintf(opt, "%s %s", value,
+			opt->boot_args);
 
-		if (check_for_global_option(kboot_ctx, name, value))
-			continue;
+	conf_strip_str(opt->boot_args);
+	conf_strip_str(opt->description);
 
-		parse_option(kboot_ctx, name, value);
-	}
+	device_add_boot_option(conf->dc->device, opt);
 }
 
+static struct conf_global_option kboot_global_options[] = {
+	{ .name = "initrd" },
+	{ .name = "root" },
+	{ .name = "video" },
+	{ .name = NULL }
+};
 
-static int kboot_parse(struct discover_context *ctx)
-{
-	static const char *const conf_names[] = {
-		"/etc/kboot.conf",
-		"/etc/kboot.cnf",
-	};
-	struct kboot_context *kboot_ctx;
-	int fd, len, rc;
-	unsigned int i;
-	struct stat stat;
-
-	rc = 0;
-	fd = -1;
-
-	kboot_ctx = talloc_zero(ctx, struct kboot_context);
-	kboot_ctx->discover = ctx;
-
-	for (i = 0, len = 0; i < sizeof(conf_names) / sizeof(conf_names[0]);
-		i++) {
-		char *filepath = resolve_path(kboot_ctx, conf_names[i],
-			ctx->device_path);
-
-		pb_log("%s: try: %s\n", __func__, filepath);
-
-		fd = open(filepath, O_RDONLY);
-		if (fd < 0) {
-			pb_log("%s: open failed: %s : %s\n", __func__, filepath,
-				strerror(errno));
-			continue;
-		}
-		if (fstat(fd, &stat)) {
-			pb_log("%s: fstat failed: %s : %s\n", __func__,
-				filepath, strerror(errno));
-			continue;
-		}
-
-		kboot_ctx->buf = talloc_array(kboot_ctx, char,
-			stat.st_size + 1);
+static const char *const kboot_conf_files[] = {
+	"/kboot.conf",
+	"/kboot.cnf",
+	"/etc/kboot.conf",
+	"/etc/kboot.cnf",
+	"/KBOOT.CONF",
+	"/KBOOT.CNF",
+	"/ETC/KBOOT.CONF",
+	"/ETC/KBOOT.CNF",
+	NULL
+};
 
-		len = read(fd, kboot_ctx->buf, stat.st_size);
-		if (len < 0) {
-			pb_log("%s: read failed: %s : %s\n", __func__, filepath,
-				strerror(errno));
-			continue;
-		}
-		kboot_ctx->buf[len] = 0;
-	}
+static const char *const kboot_ignored_names[] = {
+	"default",
+	"delay",
+	"message",
+	"timeout",
+	NULL
+};
 
-	if (len <= 0)
-		goto out;
+static int kboot_parse(struct discover_context *dc)
+{
+	struct conf_context *conf;
+	int rc;
 
-	if (!ctx->device->icon_file)
-		ctx->device->icon_file = talloc_strdup(ctx,
-				generic_icon_file(guess_device_type(ctx)));
+	conf = talloc_zero(dc, struct conf_context);
 
-	parse_buf(kboot_ctx);
+	if (!conf)
+		return -1;
 
-	rc = 1;
+	conf->dc = dc;
+	conf->global_options = kboot_global_options,
+	conf->conf_files = kboot_conf_files,
+	conf->process_pair = kboot_process_pair;
+	conf->parser_info = (void *)kboot_ignored_names,
 
-out:
-	pb_log("%s: %s\n", __func__, (rc ? "ok" : "failed"));
+	rc = conf_parse(conf);
 
-	if (fd >= 0)
-		close(fd);
-	talloc_free(kboot_ctx);
+	talloc_free(conf);
 	return rc;
 }