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;}
这个条件成立
返回
