/*
* 宏的数字变成字符串
* 1. 宏中的#的功能是将其后面的宏参数进行字符串化操作（Stringizing operator）
* 简单说就是在它引用的宏变量的左右各加上一个双引号
* 2. #@是加单引号（Charizing Operator）gcc/clang并不支持它
* 3. 宏中遇到#或##时就不会再展开宏中嵌套的宏了, 需要使用一个中间转换宏达到展开宏的目的
* 4. ##的功能，它可以拼接符号（Token-pasting operator）
*/
static void macro_as_part_of_string(void)
{
#define CONFIG_BAUDRATE 2000000
#define __STRING(x) #x /* (#x) is invalid */
#define STRING(x) __STRING(x)
#define BOOTARGS_CONSOLE "console=ttyS3,"STRING(CONFIG_BAUDRATE)"n8 "
printf("%s\n", BOOTARGS_CONSOLE);
char *pChar = "hello";
char *pChar2 = __STRING(hello); /* hello -> "hello" */
if(!strcmp(pChar, pChar2)) {
printf("pChar:%s is equal to pChar2:%s\n", pChar, pChar2);
}
/* gcc/clang not support #@
#define TOCHAR(x) #@x
char c = TOCHAR(A);
printf("c is %c\n", c);
*/
printf("%s\n", __STRING(__FILE__));
printf("%s\n", STRING(__FILE__));
#define paster(n) printf("token"#n" = %d\n", token##n)
int token9 = 100;
paster(9);
#define WIDEN2(x) L##x
#define WIDEN(x) WIDEN2(x)
#define __WFILE__ WIDEN(__FILE__)
printf("%s\n", /*L*/"hello");
}
void agentx_config_init (void)
{
int agent_role = netsnmp_ds_get_boolean (NETSNMP_DS_APPLICATION_ID,
NETSNMP_DS_AGENT_ROLE);
/*
* Common tokens for master/subagent
*/
netsnmp_register_default_domain ("agentx", "unix tcp");
netsnmp_register_default_target ("agentx", "unix", NETSNMP_AGENTX_SOCKET);
netsnmp_register_default_target ("agentx", "tcp", "localhost:" __STRING (AGENTX_PORT));
agentx_register_config_handler ("agentxsocket", agentx_parse_agentx_socket, NULL, "AgentX bind address");
#ifdef USING_AGENTX_MASTER_MODULE
/*
* tokens for master agent
*/
if (MASTER_AGENT == agent_role)
{
snmpd_register_config_handler ("master", agentx_parse_master, NULL, "specify 'agentx' for AgentX support");
agentx_register_config_handler ("agentxperms",
agentx_parse_agentx_perms, NULL,
"AgentX socket permissions: socket_perms [directory_perms [username|userid [groupname|groupid]]]");
agentx_register_config_handler ("agentxRetries", agentx_parse_agentx_retries, NULL, "AgentX Retries");
agentx_register_config_handler ("agentxTimeout", agentx_parse_agentx_timeout, NULL, "AgentX Timeout (seconds)");
}
#endif /* USING_AGENTX_MASTER_MODULE */
#ifdef USING_AGENTX_SUBAGENT_MODULE
/*
* tokens for master agent
*/
if (SUB_AGENT == agent_role)
{
/*
* set up callbacks to initiate master agent pings for this session
*/
netsnmp_ds_register_config (ASN_INTEGER,
netsnmp_ds_get_string (NETSNMP_DS_LIBRARY_ID,
NETSNMP_DS_LIB_APPTYPE),
"agentxPingInterval",
NETSNMP_DS_APPLICATION_ID, NETSNMP_DS_AGENT_AGENTX_PING_INTERVAL);
/* ping and/or reconnect by default every 15 seconds */
netsnmp_ds_set_int (NETSNMP_DS_APPLICATION_ID, NETSNMP_DS_AGENT_AGENTX_PING_INTERVAL, 15);
}
#endif /* USING_AGENTX_SUBAGENT_MODULE */
}
" mov r3, r0 /* ps_strings */ \n"
" /* Get argc, argv, and envp from stack */ \n"
" ldr r0, [sp, #0x0000] \n"
" add r1, sp, #0x0004 \n"
" add r2, r1, r0, lsl #2 \n"
" add r2, r2, #0x0004 \n"
"\n"
" /* Ensure the stack is properly aligned before calling C code. */\n"
#if 1
" bic sp, sp, #7" /*__STRING(STACKALIGNBYTES)*/ " \n"
#endif
" sub sp, sp, #8 \n"
" str r5, [sp, #4] \n"
" str r4, [sp, #0] \n"
"\n"
" b " __STRING(___start) " ");
/*
" b " __STRING(_C_LABEL(___start)) " ");
*/
void
___start(int argc, char **argv, char **envp, void *ps_strings,
const void *obj, void (*cleanup)(void))
{
char *s;
environ = envp;
if ((__progname = argv[0]) != NULL) { /* NULL ptr if argc = 0 */
if ((__progname = _strrchr(__progname, '/')) == NULL)
__progname = argv[0];
static int
bl_init(bl_t b, bool srv)
{
static int one = 1;
/* AF_UNIX address of local logger */
mode_t om;
int rv, serrno;
struct sockaddr_un *sun = &b->b_sun;
#ifndef SOCK_NONBLOCK
#define SOCK_NONBLOCK 0
#endif
#ifndef SOCK_CLOEXEC
#define SOCK_CLOEXEC 0
#endif
#ifndef SOCK_NOSIGPIPE
#define SOCK_NOSIGPIPE 0
#endif
BL_LOCK(b);
if (b->b_fd == -1) {
b->b_fd = socket(PF_LOCAL,
SOCK_DGRAM|SOCK_CLOEXEC|SOCK_NONBLOCK|SOCK_NOSIGPIPE, 0);
if (b->b_fd == -1) {
bl_log(b->b_fun, LOG_ERR, "%s: socket failed (%m)",
__func__);
BL_UNLOCK(b);
return -1;
}
#if SOCK_CLOEXEC == 0
fcntl(b->b_fd, F_SETFD, FD_CLOEXEC);
#endif
#if SOCK_NONBLOCK == 0
fcntl(b->b_fd, F_SETFL, fcntl(b->b_fd, F_GETFL) | O_NONBLOCK);
#endif
#if SOCK_NOSIGPIPE == 0
#ifdef SO_NOSIGPIPE
int o = 1;
setsockopt(b->b_fd, SOL_SOCKET, SO_NOSIGPIPE, &o, sizeof(o));
#else
signal(SIGPIPE, SIG_IGN);
#endif
#endif
}
if (bl_isconnected(b)) {
BL_UNLOCK(b);
return 0;
}
/*
* We try to connect anyway even when we are a server to verify
* that no other server is listening to the socket. If we succeed
* to connect and we are a server, someone else owns it.
*/
rv = connect(b->b_fd, (const void *)sun, (socklen_t)sizeof(*sun));
if (rv == 0) {
if (srv) {
bl_log(b->b_fun, LOG_ERR,
"%s: another daemon is handling `%s'",
__func__, sun->sun_path);
goto out;
}
} else {
if (!srv) {
/*
* If the daemon is not running, we just try a
* connect, so leave the socket alone until it does
* and only log once.
*/
if (b->b_connected != 1) {
bl_log(b->b_fun, LOG_DEBUG,
"%s: connect failed for `%s' (%m)",
__func__, sun->sun_path);
b->b_connected = 1;
}
BL_UNLOCK(b);
return -1;
}
bl_log(b->b_fun, LOG_DEBUG, "Connected to blacklist server",
__func__);
}
if (srv) {
(void)unlink(sun->sun_path);
om = umask(0);
rv = bind(b->b_fd, (const void *)sun, (socklen_t)sizeof(*sun));
serrno = errno;
(void)umask(om);
errno = serrno;
if (rv == -1) {
bl_log(b->b_fun, LOG_ERR,
"%s: bind failed for `%s' (%m)",
__func__, sun->sun_path);
goto out;
}
}
b->b_connected = 0;
#define GOT_FD 1
#if defined(LOCAL_CREDS)
#define CRED_LEVEL 0
#define CRED_NAME LOCAL_CREDS
#define CRED_SC_UID sc_euid
#define CRED_SC_GID sc_egid
#define CRED_MESSAGE SCM_CREDS
#define CRED_SIZE SOCKCREDSIZE(NGROUPS_MAX)
#define CRED_TYPE struct sockcred
#define GOT_CRED 2
#elif defined(SO_PASSCRED)
#define CRED_LEVEL SOL_SOCKET
#define CRED_NAME SO_PASSCRED
#define CRED_SC_UID uid
#define CRED_SC_GID gid
#define CRED_MESSAGE SCM_CREDENTIALS
#define CRED_SIZE sizeof(struct ucred)
#define CRED_TYPE struct ucred
#define GOT_CRED 2
#else
#define GOT_CRED 0
/*
* getpeereid() and LOCAL_PEERCRED don't help here
* because we are not a stream socket!
*/
#define CRED_SIZE 0
#define CRED_TYPE void * __unused
#endif
#ifdef CRED_LEVEL
if (setsockopt(b->b_fd, CRED_LEVEL, CRED_NAME,
&one, (socklen_t)sizeof(one)) == -1) {
bl_log(b->b_fun, LOG_ERR, "%s: setsockopt %s "
"failed (%m)", __func__, __STRING(CRED_NAME));
goto out;
}
#endif
BL_UNLOCK(b);
return 0;
out:
bl_reset(b, true);
BL_UNLOCK(b);
return -1;
}
libzfs_handle_t *
libzfs_init(void)
{
libzfs_handle_t *hdl;
#ifdef __APPLE__
struct vfsconf vfc;
struct stat sb;
int loaded;
/* Attempt to load zfs kext if its not already loaded. */
if (getvfsbyname("zfs", &vfc) != 0) {
int pick = 0;
int i;
/* Find all possible zfs kext versions. */
getkextvers(kextpaths[0], &kextvers[0]);
getkextvers(kextpaths[1], &kextvers[1]);
/* Pick the newest one. */
for (i = 0; i < 2; ++i) {
if (kextvers[i] > kextvers[pick])
pick = i;
}
loaded = load_zfs_kext(kextpaths[pick]);
ASSERT(loaded == 0);
}
/* Attempt to create "/etc/zfs" its not already there. */
if (getuid() == 0 && stat("/etc/zfs", &sb)!= 0 && errno == ENOENT)
{
(void) mkdir("/etc/zfs", 0755);
}
#endif
if ((hdl = calloc(sizeof (libzfs_handle_t), 1)) == NULL) {
return (NULL);
}
if ((hdl->libzfs_fd = open(ZFS_DEV, O_RDWR)) < 0) {
free(hdl);
return (NULL);
} else {
/* Perform special version ceck ioctl() to unlock user-kernel
* interface. This serves as protection against using userland
* tools of one implementation against kernel land of another
* implementation.
*/
zfs_cmd_t vers_zc = {0};
strncpy(vers_zc.zc_name, __STRING(MACZFS_ID), sizeof(vers_zc.zc_name)-1);
vers_zc.zc_value[0] = ZFS_IOC_NUM(ZFS_IOC__LAST_USED);
vers_zc.zc_value[1] = MACZFS_VERS_MAJOR;
vers_zc.zc_value[2] = MACZFS_VERS_MINOR;
vers_zc.zc_value[3] = MACZFS_VERS_PATCH;
hdl->libzfs_log_str = NULL;
if (zfs_ioctl(hdl, ZFS_IOC__VERSION_CHECK, &vers_zc) != 0) {
/* kernel - user version mismatch or kernel side not ready. */
free(hdl);
return (NULL);
}
}
#ifndef __APPLE__
if ((hdl->libzfs_mnttab = fopen(MNTTAB, "r")) == NULL) {
(void) close(hdl->libzfs_fd);
free(hdl);
return (NULL);
}
#endif /*!__APPLE__*/
hdl->libzfs_sharetab = fopen("/etc/dfs/sharetab", "r");
zfs_prop_init();
return (hdl);
}
