file_size = ngx_file_size(&cf->conf_file->file.info);此时 file_size=2656 当然还是和上次一样
for ( ;; ) {
if (b->pos >= b->last) {此时
b->pos =0x57759a8b77f4
b->last = 0x57759a8b8230
b->start=0x57759a8b77d0
条件不成立
ch = *b->pos++;从缓冲区
b的当前指针位置（b->pos）读取一个字符，并将指针后移一位此时 ch 是一个换行符
处于配置第3行末尾，上一次再 分号处结束，然后是一个换行
配置文件
#user nobody;
worker_processes 1;
#error_log logs/error.log;
#error_log logs/error.log notice;
#error_log logs/error.log info;
#pid logs/nginx.pid;
events {
worker_connections 1024;
}
http {
include mime.types;
default_type application/octet-stream;
#log_format main '$remote_addr - $remote_user [$time_local] "$request" '
# '$status $body_bytes_sent "$http_referer" '
# '"$http_user_agent" "$http_x_forwarded_for"';
#access_log logs/access.log main;
sendfile on;
#tcp_nopush on;
#keepalive_timeout 0;
keepalive_timeout 65;
#gzip on;
server {
listen 80;
server_name localhost;
#charset koi8-r;
#access_log logs/host.access.log main;
location / {
root html;
index index.html index.htm;
}
#error_page 404 /404.html;
# redirect server error pages to the static page /50x.html
#
error_page 500 502 503 504 /50x.html;
location = /50x.html {
root html;
}
# proxy the PHP scripts to Apache listening on 127.0.0.1:80
#
#location ~ \.php$ {
# proxy_pass http://127.0.0.1;
#}
# pass the PHP scripts to FastCGI server listening on 127.0.0.1:9000
#
#location ~ \.php$ {
# root html;
# fastcgi_pass 127.0.0.1:9000;
# fastcgi_index index.php;
# fastcgi_param SCRIPT_FILENAME /scripts$fastcgi_script_name;
# include fastcgi_params;
#}
# deny access to .htaccess files, if Apache's document root
# concurs with nginx's one
#
#location ~ /\.ht {
# deny all;
#}
}
# another virtual host using mix of IP-, name-, and port-based configuration
#
#server {
# listen 8000;
# listen somename:8080;
# server_name somename alias another.alias;
# location / {
# root html;
# index index.html index.htm;
# }
#}
# HTTPS server
#
#server {
# listen 443 ssl;
# server_name localhost;
# ssl_certificate cert.pem;
# ssl_certificate_key cert.key;
# ssl_session_cache shared:SSL:1m;
# ssl_session_timeout 5m;
# ssl_ciphers HIGH:!aNULL:!MD5;
# ssl_prefer_server_ciphers on;
# location / {
# root html;
# index index.html index.htm;
# }
#}
}
if (ch == LF) {
cf->conf_file->line++;
if (sharp_comment) {
sharp_comment = 0;
}
}此时这个条件成立
line=3 变为 line=4
sharp_comment=0 第二个条件不成立
last_space=1
if (last_space) {
start = b->pos - 1;
start_line = cf->conf_file->line;
if (ch == ' ' || ch == '\t' || ch == CR || ch == LF) {
continue;
}进入下一次循环
此时 ch 是一个换行，对应配置文件的第四行，一个空行
再次到达以上位置，
line=4 变为 line=5
然后进入下一次循环
这次 ch=#
if (last_space) {进入这个条件
然后
case '#':
sharp_comment = 1;
continue;sharp_comment = 1
进入下一次循环
ch=e
sharp_comment=1
if (sharp_comment) {
continue;
}然后进入下一次循环
ch=r
逻辑同上，因为 sharp_comment=1，这行是注释，所以会一直进入以上这个条件
直到遇到换行符
line=5 变为 line=6
进入下第6行
第6，7 行也是注释
第8行是空行，第9行是注释
然后是 空行
直到 12 行
来到12行
ch=e
sharp_comment=0
last_space=1
default:
last_space = 0;下一次循环
ch=v
逻辑同上
直到 ch= events后面的空格
else if (ch == ' ' || ch == '\t' || ch == CR || ch == LF
|| ch == ';' || ch == '{')
{
last_space = 1;
found = 1;
}然后
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++)
{把 token保存到 cf->args
word->data=events
word->len=6
然后进入下一次循环
ch={
sharp_comment=0
last_space=1
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;进入这个条件
if (ch == '{') {
return NGX_CONF_BLOCK_START;
}