android parse init.rc

[system/core/init/keyword.h]

#ifndef KEYWORD
int do_chroot(int nargs, char **args);
int do_chdir(int nargs, char **args);
int do_class_start(int nargs, char **args);
int do_class_stop(int nargs, char **args);
int do_class_reset(int nargs, char **args);
int do_domainname(int nargs, char **args);
int do_enable(int nargs, char **args);
int do_exec(int nargs, char **args);
int do_export(int nargs, char **args);
int do_hostname(int nargs, char **args);
int do_ifup(int nargs, char **args);
int do_insmod(int nargs, char **args);
int do_mkdir(int nargs, char **args);
int do_mount_all(int nargs, char **args);
int do_mount(int nargs, char **args);
int do_powerctl(int nargs, char **args);
int do_restart(int nargs, char **args);
int do_restorecon(int nargs, char **args);
int do_restorecon_recursive(int nargs, char **args);
int do_restorecon_msc(int nargs, char **args);
int do_rm(int nargs, char **args);
int do_rmdir(int nargs, char **args);
int do_setcon(int nargs, char **args);
int do_setenforce(int nargs, char **args);
int do_setkey(int nargs, char **args);
int do_setprop(int nargs, char **args);
int do_setrlimit(int nargs, char **args);
int do_setsebool(int nargs, char **args);
int do_start(int nargs, char **args);
int do_stop(int nargs, char **args);
int do_swapon_all(int nargs, char **args);
int do_trigger(int nargs, char **args);
int do_symlink(int nargs, char **args);
int do_sysclktz(int nargs, char **args);
int do_write(int nargs, char **args);
int do_copy(int nargs, char **args);
int do_chown(int nargs, char **args);
int do_chmod(int nargs, char **args);
int do_loglevel(int nargs, char **args);
int do_load_persist_props(int nargs, char **args);
int do_load_all_props(int nargs, char **args);
int do_wait(int nargs, char **args);
int do_check_fs(int nargs, char **args);

#define __MAKE_KEYWORD_ENUM__
#define KEYWORD(symbol, flags, nargs, func) K_##symbol,
enum {
K_UNKNOWN,
#endif
KEYWORD(capability,  OPTION,  0, 0)
KEYWORD(chdir,       COMMAND, 1, do_chdir)
KEYWORD(chroot,      COMMAND, 1, do_chroot)
KEYWORD(class,       OPTION,  0, 0)
KEYWORD(class_start, COMMAND, 1, do_class_start)
KEYWORD(class_stop,  COMMAND, 1, do_class_stop)
KEYWORD(class_reset, COMMAND, 1, do_class_reset)
KEYWORD(console,     OPTION,  0, 0)
KEYWORD(critical,    OPTION,  0, 0)
KEYWORD(disabled,    OPTION,  0, 0)
KEYWORD(domainname,  COMMAND, 1, do_domainname)
KEYWORD(enable,      COMMAND, 1, do_enable)
KEYWORD(exec,        COMMAND, 1, do_exec)
KEYWORD(export,      COMMAND, 2, do_export)
KEYWORD(group,       OPTION,  0, 0)
KEYWORD(hostname,    COMMAND, 1, do_hostname)
KEYWORD(ifup,        COMMAND, 1, do_ifup)
KEYWORD(insmod,      COMMAND, 1, do_insmod)
KEYWORD(import,      SECTION, 1, 0)
KEYWORD(keycodes,    OPTION,  0, 0)
KEYWORD(mkdir,       COMMAND, 1, do_mkdir)
KEYWORD(mount_all,   COMMAND, 1, do_mount_all)
KEYWORD(mount,       COMMAND, 3, do_mount)
KEYWORD(on,          SECTION, 0, 0)
KEYWORD(oneshot,     OPTION,  0, 0)
KEYWORD(onrestart,   OPTION,  0, 0)
KEYWORD(powerctl,    COMMAND, 1, do_powerctl)
KEYWORD(restart,     COMMAND, 1, do_restart)
KEYWORD(restorecon,  COMMAND, 1, do_restorecon)
KEYWORD(restorecon_recursive,  COMMAND, 1, do_restorecon_recursive)
KEYWORD(restorecon_msc,  COMMAND, 0, do_restorecon_msc)
KEYWORD(rm,          COMMAND, 1, do_rm)
KEYWORD(rmdir,       COMMAND, 1, do_rmdir)
KEYWORD(seclabel,    OPTION,  0, 0)
KEYWORD(service,     SECTION, 0, 0)
KEYWORD(setcon,      COMMAND, 1, do_setcon)
KEYWORD(setenforce,  COMMAND, 1, do_setenforce)
KEYWORD(setenv,      OPTION,  2, 0)
KEYWORD(setkey,      COMMAND, 0, do_setkey)
KEYWORD(setprop,     COMMAND, 2, do_setprop)
KEYWORD(setrlimit,   COMMAND, 3, do_setrlimit)
KEYWORD(setsebool,   COMMAND, 2, do_setsebool)
KEYWORD(socket,      OPTION,  0, 0)
KEYWORD(start,       COMMAND, 1, do_start)
KEYWORD(stop,        COMMAND, 1, do_stop)
KEYWORD(swapon_all,  COMMAND, 1, do_swapon_all)
KEYWORD(trigger,     COMMAND, 1, do_trigger)
KEYWORD(symlink,     COMMAND, 1, do_symlink)
KEYWORD(sysclktz,    COMMAND, 1, do_sysclktz)
KEYWORD(user,        OPTION,  0, 0)
KEYWORD(wait,        COMMAND, 1, do_wait)
KEYWORD(write,       COMMAND, 2, do_write)
KEYWORD(copy,        COMMAND, 2, do_copy)
KEYWORD(chown,       COMMAND, 2, do_chown)
KEYWORD(chmod,       COMMAND, 2, do_chmod)
KEYWORD(loglevel,    COMMAND, 1, do_loglevel)
KEYWORD(load_persist_props,    COMMAND, 0, do_load_persist_props)
KEYWORD(load_all_props,        COMMAND, 0, do_load_all_props)
KEYWORD(ioprio,      OPTION,  0, 0)
KEYWORD(check_fs,    COMMAND, 2, do_check_fs)
#ifdef __MAKE_KEYWORD_ENUM__
KEYWORD_COUNT,
};
#undef __MAKE_KEYWORD_ENUM__
#undef KEYWORD
#endif

[system/core/init/init_parse.c]

这里定义数组：

#include "keywords.h" //第一次是搞个枚举出来

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

static struct {
const char *name;
int (*func)(int nargs, char **args);
unsigned char nargs;
unsigned char flags;
} keyword_info[KEYWORD_COUNT] = {
[ K_UNKNOWN ] = { "unknown", 0, 0, 0 },
#include "keywords.h" //第二次搞出个数组
};
#undef KEYWORD

把这个数组展开：

todo: 插图

凡是init.rc中以service, on, import关键字开头的，讲进行分别解析。

解析section小结

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_service:
state->context = parse_service(state, nargs, args);
if (state->context) {
state->parse_line = parse_line_service;
return;
}
break;
case K_on:
state->context = parse_action(state, nargs, args);
if (state->context) {
state->parse_line = parse_line_action;
return;
}
break;
case K_import:
parse_import(state, nargs, args);
break;
}
state->parse_line = parse_line_no_op;
}