core/ngx_conf_file.c源代码分析(2)
本节我们讲述nginx配置文件相关的一些内容。
1. 配置解析相关函数实现
1) 函数ngx_conf_read_token()
static ngx_int_t
ngx_conf_read_token(ngx_conf_t *cf)
{
u_char *start, ch, *src, *dst;
off_t file_size;
size_t len;
ssize_t n, size;
ngx_uint_t found, need_space, last_space, sharp_comment, variable;
ngx_uint_t quoted, s_quoted, d_quoted, start_line;
ngx_str_t *word;
ngx_buf_t *b, *dump;
found = 0;
need_space = 0;
last_space = 1;
sharp_comment = 0;
variable = 0;
quoted = 0;
s_quoted = 0;
d_quoted = 0;
cf->args->nelts = 0;
b = cf->conf_file->buffer;
dump = cf->conf_file->dump;
start = b->pos;
start_line = cf->conf_file->line;
file_size = ngx_file_size(&cf->conf_file->file.info);
for ( ;; ) {
if (b->pos >= b->last) {
if (cf->conf_file->file.offset >= file_size) {
if (cf->args->nelts > 0 || !last_space) {
if (cf->conf_file->file.fd == NGX_INVALID_FILE) {
ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
"unexpected end of parameter, "
"expecting \";\"");
return NGX_ERROR;
}
ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
"unexpected end of file, "
"expecting \";\" or \"}\"");
return NGX_ERROR;
}
return NGX_CONF_FILE_DONE;
}
len = b->pos - start;
if (len == NGX_CONF_BUFFER) {
cf->conf_file->line = start_line;
if (d_quoted) {
ch = '"';
} else if (s_quoted) {
ch = '\'';
} else {
ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
"too long parameter \"%*s...\" started",
10, start);
return NGX_ERROR;
}
ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
"too long parameter, probably "
"missing terminating \"%c\" character", ch);
return NGX_ERROR;
}
if (len) {
ngx_memmove(b->start, start, len);
}
size = (ssize_t) (file_size - cf->conf_file->file.offset);
if (size > b->end - (b->start + len)) {
size = b->end - (b->start + len);
}
n = ngx_read_file(&cf->conf_file->file, b->start + len, size,
cf->conf_file->file.offset);
if (n == NGX_ERROR) {
return NGX_ERROR;
}
if (n != size) {
ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
ngx_read_file_n " returned "
"only %z bytes instead of %z",
n, size);
return NGX_ERROR;
}
b->pos = b->start + len;
b->last = b->pos + n;
start = b->start;
if (dump) {
dump->last = ngx_cpymem(dump->last, b->pos, size);
}
}
ch = *b->pos++;
if (ch == LF) {
cf->conf_file->line++;
if (sharp_comment) {
sharp_comment = 0;
}
}
if (sharp_comment) {
continue;
}
if (quoted) {
quoted = 0;
continue;
}
if (need_space) {
if (ch == ' ' || ch == '\t' || ch == CR || ch == LF) {
last_space = 1;
need_space = 0;
continue;
}
if (ch == ';') {
return NGX_OK;
}
if (ch == '{') {
return NGX_CONF_BLOCK_START;
}
if (ch == ')') {
last_space = 1;
need_space = 0;
} else {
ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
"unexpected \"%c\"", ch);
return NGX_ERROR;
}
}
if (last_space) {
if (ch == ' ' || ch == '\t' || ch == CR || ch == LF) {
continue;
}
start = b->pos - 1;
start_line = cf->conf_file->line;
switch (ch) {
case ';':
case '{':
if (cf->args->nelts == 0) {
ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
"unexpected \"%c\"", ch);
return NGX_ERROR;
}
if (ch == '{') {
return NGX_CONF_BLOCK_START;
}
return NGX_OK;
case '}':
if (cf->args->nelts != 0) {
ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
"unexpected \"}\"");
return NGX_ERROR;
}
return NGX_CONF_BLOCK_DONE;
case '#':
sharp_comment = 1;
continue;
case '\\':
quoted = 1;
last_space = 0;
continue;
case '"':
start++;
d_quoted = 1;
last_space = 0;
continue;
case '\'':
start++;
s_quoted = 1;
last_space = 0;
continue;
default:
last_space = 0;
}
} else {
if (ch == '{' && variable) {
continue;
}
variable = 0;
if (ch == '\\') {
quoted = 1;
continue;
}
if (ch == '$') {
variable = 1;
continue;
}
if (d_quoted) {
if (ch == '"') {
d_quoted = 0;
need_space = 1;
found = 1;
}
} else if (s_quoted) {
if (ch == '\'') {
s_quoted = 0;
need_space = 1;
found = 1;
}
} else if (ch == ' ' || ch == '\t' || ch == CR || ch == LF
|| ch == ';' || ch == '{')
{
last_space = 1;
found = 1;
}
if (found) {
word = ngx_array_push(cf->args);
if (word == NULL) {
return NGX_ERROR;
}
word->data = ngx_pnalloc(cf->pool, b->pos - 1 - start + 1);
if (word->data == NULL) {
return NGX_ERROR;
}
for (dst = word->data, src = start, len = 0;
src < b->pos - 1;
len++)
{
if (*src == '\\') {
switch (src[1]) {
case '"':
case '\'':
case '\\':
src++;
break;
case 't':
*dst++ = '\t';
src += 2;
continue;
case 'r':
*dst++ = '\r';
src += 2;
continue;
case 'n':
*dst++ = '\n';
src += 2;
continue;
}
}
*dst++ = *src++;
}
*dst = '\0';
word->len = len;
if (ch == ';') {
return NGX_OK;
}
if (ch == '{') {
return NGX_CONF_BLOCK_START;
}
found = 0;
}
}
}
}函数ngx_conf_read_token()会从配置文件中不断的读取数据，直到遇到如下情况：
-
遇到错误，返回NGX_ERROR
-
遇到以”;”结尾指令，返回NGX_OK
-
遇到以”{“开始的配置块，返回NGX_CONF_BLOCK_START
-
遇到以”}”结尾配置块，返回NGX_CONF_BLOCK_DONE
-
读取到配置文件结尾，返回NGX_CONF_FILE_DONE
下面我们来对该函数进行简单的分析：
static ngx_int_t
ngx_conf_read_token(ngx_conf_t *cf)
{
//这里b是专门为了读取配置文件开启的一块临时缓存，目前大小为4096Byte
for(;;)
{
if (b->pos >= b->last)
{
//1) 此种情况表明需要继续从配置文件中读取一部分数据到缓存中，以便进行后续的分析
}
//2) 读取一个字节的数据
ch = *b->pos++;
//3) 如果ch为换行符，且sharp_comment为真，则表明该注释行已经结束
//4) 如果当前sharp_comment为真，表明仍然为注释，则直接继续读取数据不做任何处理，直到注释行结束
//5) 如果当前quoted为真，则表明前面遇到了转义符号，此时直接继续读取数据即可
//6) 一般一对单引号或双引号之后是需要跟随空格的
if(need_space)
{
}
//7) last_space为真一般表明上次成功检测到空格，此时需要对当前ch做相应判断
if(last_space)
{
}
else{
//8) 看当前能不能凑成一个合法指令
}
}
}2) 函数ngx_conf_include()
char *
ngx_conf_include(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
{
char *rv;
ngx_int_t n;
ngx_str_t *value, file, name;
ngx_glob_t gl;
value = cf->args->elts;
file = value[1];
ngx_log_debug1(NGX_LOG_DEBUG_CORE, cf->log, 0, "include %s", file.data);
if (ngx_conf_full_name(cf->cycle, &file, 1) != NGX_OK) {
return NGX_CONF_ERROR;
}
if (strpbrk((char *) file.data, "*?[") == NULL) {
ngx_log_debug1(NGX_LOG_DEBUG_CORE, cf->log, 0, "include %s", file.data);
return ngx_conf_parse(cf, &file);
}
ngx_memzero(&gl, sizeof(ngx_glob_t));
gl.pattern = file.data;
gl.log = cf->log;
gl.test = 1;
if (ngx_open_glob(&gl) != NGX_OK) {
ngx_conf_log_error(NGX_LOG_EMERG, cf, ngx_errno,
ngx_open_glob_n " \"%s\" failed", file.data);
return NGX_CONF_ERROR;
}
rv = NGX_CONF_OK;
for ( ;; ) {
n = ngx_read_glob(&gl, &name);
if (n != NGX_OK) {
break;
}
file.len = name.len++;
file.data = ngx_pstrdup(cf->pool, &name);
if (file.data == NULL) {
return NGX_CONF_ERROR;
}
ngx_log_debug1(NGX_LOG_DEBUG_CORE, cf->log, 0, "include %s", file.data);
rv = ngx_conf_parse(cf, &file);
if (rv != NGX_CONF_OK) {
break;
}
}
ngx_close_glob(&gl);
return rv;
}这里处理include配置指令。如果不包含”*?[“这样的模式匹配字符串，则可以直接打开相应的文件进行ngx_conf_parse()处理，否则这里用到glob()函数匹配文件，再分别对每一个文件进行处理。
3) 函数ngx_conf_full_name()
ngx_int_t
ngx_conf_full_name(ngx_cycle_t *cycle, ngx_str_t *name, ngx_uint_t conf_prefix)
{
ngx_str_t *prefix;
prefix = conf_prefix ? &cycle->conf_prefix : &cycle->prefix;
return ngx_get_full_name(cycle->pool, prefix, name);
}nginx中有一个NGX_PREFIX和NGX_CONF_PREFIX，这里用于配置文件地址。如果没有指定NGX_CONF_PREFIX，则默认的配置文件地址为NGX_PREFIX/conf/nginx.conf。
4) 函数ngx_conf_open_file()
ngx_open_file_t *
ngx_conf_open_file(ngx_cycle_t *cycle, ngx_str_t *name)
{
ngx_str_t full;
ngx_uint_t i;
ngx_list_part_t *part;
ngx_open_file_t *file;
#if (NGX_SUPPRESS_WARN)
ngx_str_null(&full);
#endif
if (name->len) {
full = *name;
if (ngx_conf_full_name(cycle, &full, 0) != NGX_OK) {
return NULL;
}
part = &cycle->open_files.part;
file = part->elts;
for (i = 0; /* void */ ; i++) {
if (i >= part->nelts) {
if (part->next == NULL) {
break;
}
part = part->next;
file = part->elts;
i = 0;
}
if (full.len != file[i].name.len) {
continue;
}
if (ngx_strcmp(full.data, file[i].name.data) == 0) {
return &file[i];
}
}
}
file = ngx_list_push(&cycle->open_files);
if (file == NULL) {
return NULL;
}
if (name->len) {
file->fd = NGX_INVALID_FILE;
file->name = full;
} else {
file->fd = ngx_stderr;
file->name = *name;
}
file->flush = NULL;
file->data = NULL;
return file;
}这里如果提供了name的话(即name->len>0)，则首先从cycle->open_files链表中查看该文件是否打开过，如果找到则直接返回该文件；否则向该链表中添加一条记录。这里name->len为0的话，则表明打开的是一个标准错误输出文件。
5) 函数ngx_conf_flush_files()
static void
ngx_conf_flush_files(ngx_cycle_t *cycle)
{
ngx_uint_t i;
ngx_list_part_t *part;
ngx_open_file_t *file;
ngx_log_debug0(NGX_LOG_DEBUG_CORE, cycle->log, 0, "flush files");
part = &cycle->open_files.part;
file = part->elts;
for (i = 0; /* void */ ; i++) {
if (i >= part->nelts) {
if (part->next == NULL) {
break;
}
part = part->next;
file = part->elts;
i = 0;
}
if (file[i].flush) {
file[i].flush(&file[i], cycle->log);
}
}
}对所有已打开文件调用对应的flush()方法刷新文件。
6) 函数ngx_conf_log_error()
void ngx_cdecl
ngx_conf_log_error(ngx_uint_t level, ngx_conf_t *cf, ngx_err_t err,
const char *fmt, ...)
{
u_char errstr[NGX_MAX_CONF_ERRSTR], *p, *last;
va_list args;
last = errstr + NGX_MAX_CONF_ERRSTR;
va_start(args, fmt);
p = ngx_vslprintf(errstr, last, fmt, args);
va_end(args);
if (err) {
p = ngx_log_errno(p, last, err);
}
if (cf->conf_file == NULL) {
ngx_log_error(level, cf->log, 0, "%*s", p - errstr, errstr);
return;
}
if (cf->conf_file->file.fd == NGX_INVALID_FILE) {
ngx_log_error(level, cf->log, 0, "%*s in command line",
p - errstr, errstr);
return;
}
ngx_log_error(level, cf->log, 0, "%*s in %s:%ui",
p - errstr, errstr,
cf->conf_file->file.name.data, cf->conf_file->line);
}用于打印配置文件检查时发现的相应错误。
7) 函数ngx_conf_set_flag_slot()
char *
ngx_conf_set_flag_slot(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
{
char *p = conf;
ngx_str_t *value;
ngx_flag_t *fp;
ngx_conf_post_t *post;
fp = (ngx_flag_t *) (p + cmd->offset);
if (*fp != NGX_CONF_UNSET) {
return "is duplicate";
}
value = cf->args->elts;
if (ngx_strcasecmp(value[1].data, (u_char *) "on") == 0) {
*fp = 1;
} else if (ngx_strcasecmp(value[1].data, (u_char *) "off") == 0) {
*fp = 0;
} else {
ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
"invalid value \"%s\" in \"%s\" directive, "
"it must be \"on\" or \"off\"",
value[1].data, cmd->name.data);
return NGX_CONF_ERROR;
}
if (cmd->post) {
post = cmd->post;
return post->post_handler(cf, post, fp);
}
return NGX_CONF_OK;
}这里conf是该命令对应模块所关联着的上下文对象，例如对于ngx_core_module，其所关联的上下文对象就为ngx_core_conf_t。请参看：conf_ctx 4级指针结构。
这里即通过命令设置conf对应字段的值。
8) 函数ngx_conf_set_str_slot()
char *
ngx_conf_set_str_slot(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
{
char *p = conf;
ngx_str_t *field, *value;
ngx_conf_post_t *post;
field = (ngx_str_t *) (p + cmd->offset);
if (field->data) {
return "is duplicate";
}
value = cf->args->elts;
*field = value[1];
if (cmd->post) {
post = cmd->post;
return post->post_handler(cf, post, field);
}
return NGX_CONF_OK;
}设置字符串字段的值。
9) 函数ngx_conf_set_str_array_slot()
char *
ngx_conf_set_str_array_slot(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
{
char *p = conf;
ngx_str_t *value, *s;
ngx_array_t **a;
ngx_conf_post_t *post;
a = (ngx_array_t **) (p + cmd->offset);
if (*a == NGX_CONF_UNSET_PTR) {
*a = ngx_array_create(cf->pool, 4, sizeof(ngx_str_t));
if (*a == NULL) {
return NGX_CONF_ERROR;
}
}
s = ngx_array_push(*a);
if (s == NULL) {
return NGX_CONF_ERROR;
}
value = cf->args->elts;
*s = value[1];
if (cmd->post) {
post = cmd->post;
return post->post_handler(cf, post, s);
}
return NGX_CONF_OK;
}conf上下文中某个字段类型为字符串数组类型，通过此函数往该数组中添加元素。
10) 函数ngx_conf_set_keyval_slot()
char *
ngx_conf_set_keyval_slot(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
{
char *p = conf;
ngx_str_t *value;
ngx_array_t **a;
ngx_keyval_t *kv;
ngx_conf_post_t *post;
a = (ngx_array_t **) (p + cmd->offset);
if (*a == NULL) {
*a = ngx_array_create(cf->pool, 4, sizeof(ngx_keyval_t));
if (*a == NULL) {
return NGX_CONF_ERROR;
}
}
kv = ngx_array_push(*a);
if (kv == NULL) {
return NGX_CONF_ERROR;
}
value = cf->args->elts;
kv->key = value[1];
kv->value = value[2];
if (cmd->post) {
post = cmd->post;
return post->post_handler(cf, post, kv);
}
return NGX_CONF_OK;
}设置key/value值。
11) 函数ngx_conf_set_num_slot()
char *
ngx_conf_set_num_slot(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
{
char *p = conf;
ngx_int_t *np;
ngx_str_t *value;
ngx_conf_post_t *post;
np = (ngx_int_t *) (p + cmd->offset);
if (*np != NGX_CONF_UNSET) {
return "is duplicate";
}
value = cf->args->elts;
*np = ngx_atoi(value[1].data, value[1].len);
if (*np == NGX_ERROR) {
return "invalid number";
}
if (cmd->post) {
post = cmd->post;
return post->post_handler(cf, post, np);
}
return NGX_CONF_OK;
}conf上下文中某个字段类型为ngx_int_t类型，通过本函数设置cmd所关联的上下文该字段的值。
12) 函数ngx_conf_set_size_slot()
char *
ngx_conf_set_size_slot(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
{
char *p = conf;
size_t *sp;
ngx_str_t *value;
ngx_conf_post_t *post;
sp = (size_t *) (p + cmd->offset);
if (*sp != NGX_CONF_UNSET_SIZE) {
return "is duplicate";
}
value = cf->args->elts;
*sp = ngx_parse_size(&value[1]);
if (*sp == (size_t) NGX_ERROR) {
return "invalid value";
}
if (cmd->post) {
post = cmd->post;
return post->post_handler(cf, post, sp);
}
return NGX_CONF_OK;
}conf上下文中某个字段类型为size类型，通过本函数设置cmd所关联的上下文该字段的值。
查看ngx_parse_size()函数，目前支持的单位有： K/k, M/m，默认的字节单位 比如设置某一个字段为： 10K，则最后会被转换为10*1024
13) 函数ngx_conf_set_off_slot()
char *
ngx_conf_set_off_slot(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
{
char *p = conf;
off_t *op;
ngx_str_t *value;
ngx_conf_post_t *post;
op = (off_t *) (p + cmd->offset);
if (*op != NGX_CONF_UNSET) {
return "is duplicate";
}
value = cf->args->elts;
*op = ngx_parse_offset(&value[1]);
if (*op == (off_t) NGX_ERROR) {
return "invalid value";
}
if (cmd->post) {
post = cmd->post;
return post->post_handler(cf, post, op);
}
return NGX_CONF_OK;
}conf上下文中某个字段类型为offset类型，通过本函数设置cmd所关联的上下文该字段的值。当前支持的单位有：K/M/G
14) 函数ngx_conf_set_msec_slot()
char *
ngx_conf_set_msec_slot(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
{
char *p = conf;
ngx_msec_t *msp;
ngx_str_t *value;
ngx_conf_post_t *post;
msp = (ngx_msec_t *) (p + cmd->offset);
if (*msp != NGX_CONF_UNSET_MSEC) {
return "is duplicate";
}
value = cf->args->elts;
*msp = ngx_parse_time(&value[1], 0);
if (*msp == (ngx_msec_t) NGX_ERROR) {
return "invalid value";
}
if (cmd->post) {
post = cmd->post;
return post->post_handler(cf, post, msp);
}
return NGX_CONF_OK;
}conf上下文中某个字段类型为时间类型，通过本函数设置cmd所关联的上下文该字段的值。例如：2001y 1M 1d表示为2001年1月1日。
15) 函数ngx_conf_set_sec_slot()
char *
ngx_conf_set_sec_slot(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
{
char *p = conf;
time_t *sp;
ngx_str_t *value;
ngx_conf_post_t *post;
sp = (time_t *) (p + cmd->offset);
if (*sp != NGX_CONF_UNSET) {
return "is duplicate";
}
value = cf->args->elts;
*sp = ngx_parse_time(&value[1], 1);
if (*sp == (time_t) NGX_ERROR) {
return "invalid value";
}
if (cmd->post) {
post = cmd->post;
return post->post_handler(cf, post, sp);
}
return NGX_CONF_OK;
}conf上下文中某个字段类型为时间类型，通过本函数设置cmd所关联的上下文该字段的值。
16) 函数ngx_conf_set_bufs_slot()
char *
ngx_conf_set_bufs_slot(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
{
char *p = conf;
ngx_str_t *value;
ngx_bufs_t *bufs;
bufs = (ngx_bufs_t *) (p + cmd->offset);
if (bufs->num) {
return "is duplicate";
}
value = cf->args->elts;
bufs->num = ngx_atoi(value[1].data, value[1].len);
if (bufs->num == NGX_ERROR || bufs->num == 0) {
return "invalid value";
}
bufs->size = ngx_parse_size(&value[2]);
if (bufs->size == (size_t) NGX_ERROR || bufs->size == 0) {
return "invalid value";
}
return NGX_CONF_OK;
}设置一个ngx_bufs_t数据。
17) 函数ngx_conf_set_enum_slot()
char *
ngx_conf_set_enum_slot(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
{
char *p = conf;
ngx_uint_t *np, i;
ngx_str_t *value;
ngx_conf_enum_t *e;
np = (ngx_uint_t *) (p + cmd->offset);
if (*np != NGX_CONF_UNSET_UINT) {
return "is duplicate";
}
value = cf->args->elts;
e = cmd->post;
for (i = 0; e[i].name.len != 0; i++) {
if (e[i].name.len != value[1].len
|| ngx_strcasecmp(e[i].name.data, value[1].data) != 0)
{
continue;
}
*np = e[i].value;
return NGX_CONF_OK;
}
ngx_conf_log_error(NGX_LOG_WARN, cf, 0,
"invalid value \"%s\"", value[1].data);
return NGX_CONF_ERROR;
}设置一个枚举类型值。
18） 函数ngx_conf_set_bitmask_slot()
char *
ngx_conf_set_bitmask_slot(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
{
char *p = conf;
ngx_uint_t *np, i, m;
ngx_str_t *value;
ngx_conf_bitmask_t *mask;
np = (ngx_uint_t *) (p + cmd->offset);
value = cf->args->elts;
mask = cmd->post;
for (i = 1; i < cf->args->nelts; i++) {
for (m = 0; mask[m].name.len != 0; m++) {
if (mask[m].name.len != value[i].len
|| ngx_strcasecmp(mask[m].name.data, value[i].data) != 0)
{
continue;
}
if (*np & mask[m].mask) {
ngx_conf_log_error(NGX_LOG_WARN, cf, 0,
"duplicate value \"%s\"", value[i].data);
} else {
*np |= mask[m].mask;
}
break;
}
if (mask[m].name.len == 0) {
ngx_conf_log_error(NGX_LOG_WARN, cf, 0,
"invalid value \"%s\"", value[i].data);
return NGX_CONF_ERROR;
}
}
return NGX_CONF_OK;
}设置掩码位。
19） 函数ngx_conf_deprecated()
#if 0
char *
ngx_conf_unsupported(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
{
return "unsupported on this platform";
}
#endif
char *
ngx_conf_deprecated(ngx_conf_t *cf, void *post, void *data)
{
ngx_conf_deprecated_t *d = post;
ngx_conf_log_error(NGX_LOG_WARN, cf, 0,
"the \"%s\" directive is deprecated, "
"use the \"%s\" directive instead",
d->old_name, d->new_name);
return NGX_CONF_OK;
}这里主要是打印相关提示，说明某一个指令已经过时。
20) 函数ngx_conf_check_num_bounds()
char *
ngx_conf_check_num_bounds(ngx_conf_t *cf, void *post, void *data)
{
ngx_conf_num_bounds_t *bounds = post;
ngx_int_t *np = data;
if (bounds->high == -1) {
if (*np >= bounds->low) {
return NGX_CONF_OK;
}
ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
"value must be equal to or greater than %i",
bounds->low);
return NGX_CONF_ERROR;
}
if (*np >= bounds->low && *np <= bounds->high) {
return NGX_CONF_OK;
}
ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
"value must be between %i and %i",
bounds->low, bounds->high);
return NGX_CONF_ERROR;
}主要是用于检查所设定的值是否在某个区间范围内。
[参看]
