file_size = ngx_file_size(&cf->conf_file->file.info);
获取 配置文件的大小
此时
file_size=364
for ( ;; ) {
if (b->pos >= b->last) {
此时
b->pos =0x5cd4701487e4
b->last =0x5cd47014893c
b->start=0x5cd4701487d0
条件不成立
ch = *b->pos++;
从缓冲区的当前处理位置获取 一个字符，然后指针后移为下一个字符的处理做准备
此时
ch=（换行符）
配置文件 nginx.conf
worker_processes 1;
events {
worker_connections 1024;
}
http {
server {
listen 80;
server_name localhost;
location / {
root html;
index index.html index.htm;
}
error_page 500 502 503 504 /50x.html;
location = /50x.html {
root html;
}
}
}
这次处理到第一行的末尾 分号之后的换行符
if (ch == LF) {
cf->conf_file->line++;
if (sharp_comment) {
sharp_comment = 0;
}
}
此时 条件成立
此时
line=1 变为 line=2 进入第二行
sharp_comment=0 条件不成立
if (sharp_comment) {
continue;
}
此时
sharp_comment=0
if (quoted) {
quoted = 0;
continue;
}
此时
quoted=0
if (need_space) {
此时
need_space=0
if (last_space) {
此时
last_space=1
start = b->pos - 1;
start_line = cf->conf_file->line;
更新 单词开始位置的记录
此时
start_line=2
if (ch == ' ' || ch == '\t' || ch == CR || ch == LF) {
continue;
}
上一个字符是分隔符，这次还是分隔符，跳过这个字符的后续处理
进入下一次循环，处理下一个字符
for ( ;; ) {
if (b->pos >= b->last) {
此时
b->pos =0x64b74246e7e5
b->last =0x64b74246e93c
b->start=0x64b74246e7d0
条件不成立
ch = *b->pos++;
此时
ch=（换行符）
第二行是一个空行，只有一个换行符
if (ch == LF) {
cf->conf_file->line++;
if (sharp_comment) {
sharp_comment = 0;
}
}
此时
line=2 变为 line=3 进入第三行
sharp_comment=0 条件不成立
if (sharp_comment) {
continue;
}
此时
sharp_comment=0
if (quoted) {
quoted = 0;
continue;
}
此时
quoted=0
if (need_space) {
此时
need_space=0
if (last_space) {
此时
last_space=1
start = b->pos - 1;
start_line = cf->conf_file->line;
此时
start_line=3
if (ch == ' ' || ch == '\t' || ch == CR || ch == LF) {
continue;
}
此时 条件成立，进入下一次循环
for ( ;; ) {
if (b->pos >= b->last) {
此时
b->pos =0x64b74246e7e6
b->last =0x64b74246e93c
b->start=0x64b74246e7d0
条件不成立
ch = *b->pos++;
此时
ch=e
if (ch == LF) {
cf->conf_file->line++;
if (sharp_comment) {
sharp_comment = 0;
}
}
此时
条件不成立
if (sharp_comment) {
continue;
}
此时
sharp_comment=0
if (quoted) {
quoted = 0;
continue;
}
此时
quoted=0
if (need_space) {
此时
need_space=0
if (last_space) {
此时
last_space=1
start = b->pos - 1;
start_line = cf->conf_file->line;
此时
start_line=3
if (ch == ' ' || ch == '\t' || ch == CR || ch == LF) {
continue;
}
此时
条件不成立
switch (ch) {
进入这个分支
default:
last_space = 0;
进入下一次循环
for ( ;; ) {
if (b->pos >= b->last) {
此时
b->pos =0x64b74246e7e7
b->last =0x64b74246e93c
b->start=0x64b74246e7d0
条件不成立
ch = *b->pos++;
此时
ch=v
if (ch == LF) {
cf->conf_file->line++;
if (sharp_comment) {
sharp_comment = 0;
}
}
此时
条件不成立
if (sharp_comment) {
continue;
}
此时
sharp_comment=0
if (quoted) {
quoted = 0;
continue;
}
此时
quoted=0
if (need_space) {
此时
need_space=0
if (last_space) {
此时
last_space=0
} else {
if (ch == '{' && variable) {
continue;
}
variable = 0;
if (ch == '\\') {
quoted = 1;
continue;
}
if (ch == '$') {
variable = 1;
continue;
}
此时 条件不成立
if (d_quoted) {
if (ch == '"') {
d_quoted = 0;
need_space = 1;
found = 1;
}
} else if (s_quoted) {
if (ch == '\'') {
s_quoted = 0;
need_space = 1;
found = 1;
}
} else if (ch == ' ' || ch == '\t' || ch == CR || ch == LF
|| ch == ';' || ch == '{')
{
last_space = 1;
found = 1;
}
此时
d_quoted=0
s_quoted=0
条件不成立
if (found) {
此时
found=0
重复以上逻辑
接下来
ch=e
ch=n
ch=t
ch=s
ch= (空格)
if (ch == LF) {
cf->conf_file->line++;
if (sharp_comment) {
sharp_comment = 0;
}
}
if (sharp_comment) {
continue;
}
if (quoted) {
quoted = 0;
continue;
}
if (need_space) {
此时
sharp_comment=0
quoted=0
need_space=0
以上条件不成立
if (last_space) {
last_space=0
} else {
if (ch == '{' && variable) {
continue;
}
variable = 0;
if (ch == '\\') {
quoted = 1;
continue;
}
if (ch == '$') {
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;
}
此时
d_quoted=0
s_quoted=0
条件不成立
} else if (ch == ' ' || ch == '\t' || ch == CR || ch == LF
|| ch == ';' || ch == '{')
{
last_space = 1;
found = 1;
}
此时
ch= 空格
last_space = 1 标记此次字符是分隔符
found = 1; 表示找到了一个单词
if (found) {
此时
found=1
word = ngx_array_push(cf->args);
if (word == NULL) {
return NGX_ERROR;
}
获取新元素
word->data = ngx_pnalloc(cf->pool, b->pos - 1 - start + 1);
if (word->data == NULL) {
return NGX_ERROR;
}
为单词分配内存
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;
复制单词到 word
此时
word->data=events
word->len=6
if (ch == ';') {
return NGX_OK;
}
if (ch == '{') {
return NGX_CONF_BLOCK_START;
}
found = 0;
此时 条件不成立
found 重置为0
进入下一次循环
ch={
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) {
此时
sharp_comment=0
quoted=0
need_space=0
以上条件不成立
if (last_space) {
此时
last_space=1
start = b->pos - 1;
start_line = cf->conf_file->line;
if (ch == ' ' || ch == '\t' || ch == CR || ch == LF) {
continue;
}
此时
条件不成立
switch (ch) {
进入以下分支
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;
此时
cf->args->nelts=1
返回 NGX_CONF_BLOCK_START
表示此次以 { 为结束
