am b2406973: Merge changes I727d9135,I3bd1b59d,I0d05aa28 (5ebd8e43) · Commits · e / os / android_system_core

init/devices.c

+63 −20

Original line number	Diff line number	Diff line
		@@ -44,6 +44,7 @@
		#include <cutils/uevent.h>

		#include "devices.h"
		#include "ueventd_parser.h"
		#include "util.h"
		#include "log.h"

		@@ -530,8 +531,11 @@ static const char parse_device_name(struct uevent uevent, unsigned int len)
		name++;

		/* too-long names would overrun our buffer */
		if(strlen(name) > len)
		if(strlen(name) > len) {
		ERROR("DEVPATH=%s exceeds %u-character limit on filename; ignoring event\n",
		name, len);
		return NULL;
		}

		return name;
		}
		@@ -557,37 +561,76 @@ static void handle_block_device_event(struct uevent *uevent)
		uevent->major, uevent->minor, links);
		}

		#define DEVPATH_LEN 96

		static bool assemble_devpath(char devpath, const char dirname,
		const char *devname)
		{
		int s = snprintf(devpath, DEVPATH_LEN, "%s/%s", dirname, devname);
		if (s < 0) {
		ERROR("failed to assemble device path (%s); ignoring event\n",
		strerror(errno));
		return false;
		} else if (s >= DEVPATH_LEN) {
		ERROR("%s/%s exceeds %u-character limit on path; ignoring event\n",
		dirname, devname, DEVPATH_LEN);
		return false;
		}
		return true;
		}

		static void mkdir_recursive_for_devpath(const char *devpath)
		{
		char dir[DEVPATH_LEN];
		char *slash;

		strcpy(dir, devpath);
		slash = strrchr(dir, '/');
		*slash = '\0';
		mkdir_recursive(dir, 0755);
		}

		static void handle_generic_device_event(struct uevent *uevent)
		{
		char *base;
		const char *name;
		char devpath[96] = {0};
		char devpath[DEVPATH_LEN] = {0};
		char **links = NULL;

		name = parse_device_name(uevent, 64);
		if (!name)
		return;

		if (!strncmp(uevent->subsystem, "usb", 3)) {
		struct ueventd_subsystem *subsystem =
		ueventd_subsystem_find_by_name(uevent->subsystem);

		if (subsystem) {
		const char *devname;

		switch (subsystem->devname_src) {
		case DEVNAME_UEVENT_DEVNAME:
		devname = uevent->device_name;
		break;

		case DEVNAME_UEVENT_DEVPATH:
		devname = name;
		break;

		default:
		ERROR("%s subsystem's devpath option is not set; ignoring event\n",
		uevent->subsystem);
		return;
		}

		if (!assemble_devpath(devpath, subsystem->dirname, devname))
		return;
		mkdir_recursive_for_devpath(devpath);
		} else if (!strncmp(uevent->subsystem, "usb", 3)) {
		if (!strcmp(uevent->subsystem, "usb")) {
		if (uevent->device_name) {
		/*
		* create device node provided by kernel if present
		* see drivers/base/core.c
		*/
		char *p = devpath;
		snprintf(devpath, sizeof(devpath), "/dev/%s", uevent->device_name);
		/* skip leading /dev/ */
		p += 5;
		/* build directories */
		while (*p) {
		if (*p == '/') {
		*p = 0;
		make_dir(devpath, 0755);
		*p = '/';
		}
		p++;
		}
		if (!assemble_devpath(devpath, "/dev", uevent->device_name))
		return;
		mkdir_recursive_for_devpath(devpath);
		}
		else {
		/* This imitates the file system that would be created

init/ueventd.h

+15 −0

Original line number	Diff line number	Diff line
		@@ -17,6 +17,21 @@
		#ifndef _INIT_UEVENTD_H_
		#define _INIT_UEVENTD_H_

		#include <cutils/list.h>
		#include <sys/types.h>

		struct ueventd_subsystem {
		struct listnode slist;

		const char *name;
		enum {
		DEVNAME_UNKNOWN = 0,
		DEVNAME_UEVENT_DEVNAME,
		DEVNAME_UEVENT_DEVPATH,
		} devname_src;
		const char *dirname;
		};

		int ueventd_main(int argc, char **argv);

		#endif

init/ueventd_keywords.h

0 → 100644

+15 −0

Original line number	Diff line number	Diff line
		#ifndef KEYWORD
		#define __MAKE_KEYWORD_ENUM__
		#define KEYWORD(symbol, flags, nargs) K_##symbol,
		enum {
		K_UNKNOWN,
		#endif
		KEYWORD(subsystem, SECTION, 1)
		KEYWORD(devname, OPTION, 1)
		KEYWORD(dirname, OPTION, 1)
		#ifdef __MAKE_KEYWORD_ENUM__
		KEYWORD_COUNT,
		};
		#undef __MAKE_KEYWORD_ENUM__
		#undef KEYWORD
		#endif

init/ueventd_parser.c

+177 −4

Original line number	Diff line number	Diff line
		@@ -14,18 +14,189 @@
		* limitations under the License.
		*/

		#include <ctype.h>
		#include <errno.h>
		#include <stdio.h>
		#include <unistd.h>
		#include <stdarg.h>
		#include <stdlib.h>
		#include <string.h>

		#include "ueventd.h"
		#include "ueventd_parser.h"
		#include "parser.h"
		#include "log.h"
		#include "util.h"

		static list_declare(subsystem_list);

		static void parse_line_device(struct parse_state state, int nargs, char *args);

		#define SECTION 0x01
		#define OPTION 0x02

		#include "ueventd_keywords.h"

		#define KEYWORD(symbol, flags, nargs) \
		[ K_##symbol ] = { #symbol, nargs + 1, flags, },

		static struct {
		const char *name;
		unsigned char nargs;
		unsigned char flags;
		} keyword_info[KEYWORD_COUNT] = {
		[ K_UNKNOWN ] = { "unknown", 0, 0 },
		#include "ueventd_keywords.h"
		};
		#undef KEYWORD

		#define kw_is(kw, type) (keyword_info[kw].flags & (type))
		#define kw_nargs(kw) (keyword_info[kw].nargs)

		static int lookup_keyword(const char *s)
		{
		switch (*s++) {
		case 'd':
		if (!strcmp(s, "evname")) return K_devname;
		if (!strcmp(s, "irname")) return K_dirname;
		break;
		case 's':
		if (!strcmp(s, "ubsystem")) return K_subsystem;
		break;
		}
		return K_UNKNOWN;
		}

		static void parse_line_no_op(struct parse_state *state __attribute__((unused)),
		int nargs __attribute__((unused)), char **args __attribute__((unused)))
		{
		}

		static int valid_name(const char *name)
		{
		while (*name) {
		if (!isalnum(name) && (name != '_') && (*name != '-')) {
		return 0;
		}
		name++;
		}
		return 1;
		}

		struct ueventd_subsystem ueventd_subsystem_find_by_name(const char name)
		{
		struct listnode *node;
		struct ueventd_subsystem *s;

		list_for_each(node, &subsystem_list) {
		s = node_to_item(node, struct ueventd_subsystem, slist);
		if (!strcmp(s->name, name)) {
		return s;
		}
		}
		return 0;
		}

		static void parse_subsystem(struct parse_state state,
		int nargs __attribute__((unused)), char **args)
		{
		struct ueventd_subsystem *s;

		if (!valid_name(args[1])) {
		parse_error(state, "invalid subsystem name '%s'\n", args[1]);
		return 0;
		}

		s = ueventd_subsystem_find_by_name(args[1]);
		if (s) {
		parse_error(state, "ignored duplicate definition of subsystem '%s'\n",
		args[1]);
		return 0;
		}

		s = calloc(1, sizeof(*s));
		if (!s) {
		parse_error(state, "out of memory\n");
		return 0;
		}
		s->name = args[1];
		s->dirname = "/dev";
		list_add_tail(&subsystem_list, &s->slist);
		return s;
		}

		static void parse_line_subsystem(struct parse_state *state, int nargs,
		char **args)
		{
		struct ueventd_subsystem *s = state->context;
		int kw;

		if (nargs == 0) {
		return;
		}

		kw = lookup_keyword(args[0]);
		switch (kw) {
		case K_devname:
		if (!strcmp(args[1], "uevent_devname"))
		s->devname_src = DEVNAME_UEVENT_DEVNAME;
		else if (!strcmp(args[1], "uevent_devpath"))
		s->devname_src = DEVNAME_UEVENT_DEVPATH;
		else
		parse_error(state, "invalid devname '%s'\n", args[1]);
		break;

		case K_dirname:
		if (args[1][0] == '/')
		s->dirname = args[1];
		else
		parse_error(state, "dirname '%s' does not start with '/'\n",
		args[1]);
		break;

		default:
		parse_error(state, "invalid option '%s'\n", args[0]);
		}
		}

		static void parse_new_section(struct parse_state *state, int kw,
		int nargs, char **args)
		{
		printf("[ %s %s ]\n", args[0],
		nargs > 1 ? args[1] : "");

		switch(kw) {
		case K_subsystem:
		state->context = parse_subsystem(state, nargs, args);
		if (state->context) {
		state->parse_line = parse_line_subsystem;
		return;
		}
		break;
		}
		state->parse_line = parse_line_no_op;
		}

		static void parse_line(struct parse_state state, char *args, int nargs)
		{
		int kw = lookup_keyword(args[0]);
		int kw_nargs = kw_nargs(kw);

		if (nargs < kw_nargs) {
		parse_error(state, "%s requires %d %s\n", args[0], kw_nargs - 1,
		kw_nargs > 2 ? "arguments" : "argument");
		return;
		}

		if (kw_is(kw, SECTION)) {
		parse_new_section(state, kw, nargs, args);
		} else if (kw_is(kw, OPTION)) {
		state->parse_line(state, nargs, args);
		} else {
		parse_line_device(state, nargs, args);
		}
		}

		static void parse_config(const char fn, char s)
		{
		struct parse_state state;
		@@ -36,18 +207,19 @@ static void parse_config(const char fn, char s)
		state.line = 1;
		state.ptr = s;
		state.nexttoken = 0;
		state.parse_line = parse_line_device;
		state.parse_line = parse_line_no_op;
		for (;;) {
		int token = next_token(&state);
		switch (token) {
		case T_EOF:
		state.parse_line(&state, 0, 0);
		parse_line(&state, args, nargs);
		return;
		case T_NEWLINE:
		if (nargs) {
		state.parse_line(&state, nargs, args);
		parse_line(&state, args, nargs);
		nargs = 0;
		}
		state.line++;
		break;
		case T_TEXT:
		if (nargs < UEVENTD_PARSER_MAXARGS) {
		@@ -69,7 +241,8 @@ int ueventd_parse_config_file(const char *fn)
		return 0;
		}

		static void parse_line_device(struct parse_state* state, int nargs, char **args)
		static void parse_line_device(struct parse_state *state __attribute__((unused)),
		int nargs, char **args)
		{
		set_device_permission(nargs, args);
		}

init/ueventd_parser.h

+3 −0

Original line number	Diff line number	Diff line
		@@ -17,9 +17,12 @@
		#ifndef _INIT_UEVENTD_PARSER_H_
		#define _INIT_UEVENTD_PARSER_H_

		#include "ueventd.h"

		#define UEVENTD_PARSER_MAXARGS 5

		int ueventd_parse_config_file(const char *fn);
		void set_device_permission(int nargs, char **args);
		struct ueventd_subsystem ueventd_subsystem_find_by_name(const char name);

		#endif