Micro_httpd

版权声明本站原创文章由萌叔发表转载请注明萌叔 | http://vearne.cc 安装&配置安装请参考参考资料1和2 安装完成以后，可以使用man micro_httpd 来获得更详细的说明执行流程代码解析 micro_httpd /* micro_httpd - really small HTTP server ** ** Copyright � 1999,2005 by Jef Poskanzer <jef@mail.acme.com>. ** All rights reserved. ** ** Redistribution and use in source and binary forms, with or without ** modification, are permitted provided that the following conditions ** are met: ** 1. Redistributions of source code must retain the above copyright ** notice, this list of conditions and the following disclaimer. ** 2. Redistributions in binary form must reproduce the above copyright ** notice, this list of conditions and the following disclaimer in the ** documentation and/or other materials provided with the distribution. ** ** THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND ** ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE ** IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ** ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE ** FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL ** DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS ** OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) ** HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT ** LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY ** OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF ** SUCH DAMAGE. */ /* ####################################### 1.此程序对输入输出使用的是stdin和stdout 可以猜测它需要依赖其它程序对它的输入输出进行重定向 2.次程序没有创建socket服务因此需要其它程序为其创建socket服务 ###################################### */ #include <sys/types.h> #include <unistd.h> #include <stdlib.h> #include <stdio.h> #include <string.h> #include <dirent.h> #include <ctype.h> #include <time.h> #include <sys/stat.h> #define SERVER_NAME "micro_httpd" #define SERVER_URL "http://www.acme.com/software/micro_httpd/" #define PROTOCOL "HTTP/1.0" #define RFC1123FMT "%a, %d %b %Y %H:%M:%S GMT" /* Forwards. */ //输出文件相关属性的详细信息 static void file_details( char* dir, char* name ); //返回出错页面 static void send_error( int status, char* title, char* extra_header, char* text ); //设置reponse static void send_headers( int status, char* title, char* extra_header, char* mime_type, off_t length, time_t mod ); //通过文件名推断文件mime_type static char* get_mime_type( char* name ); //URL 解码 static void strdecode( char* to, char* from ); //十六进制转换为十进制数 static int hexit( char c ); //用于文件名编码 static void strencode( char* to, size_t tosize, const char* from ); int main( int argc, char** argv ) { char line[10000], method[10000], path[10000], protocol[10000], idx[20000], location[20000], command[20000]; char* file; size_t len; int ich; struct stat sb; FILE* fp; struct dirent **dl; int i, n; if ( argc != 2 ) send_error( 500, "Internal Error", (char*) 0, "Config error - no dir specified." ); //更改工作目录 if ( chdir( argv[1] ) < 0 ) send_error( 500, "Internal Error", (char*) 0, "Config error - couldn't chdir()." ); if ( fgets( line, sizeof(line), stdin ) == (char*) 0 ) send_error( 400, "Bad Request", (char*) 0, "No request found." ); //解析请求形如 GET /abc/index.html HTTP/1.0 if ( sscanf( line, "%[^ ] %[^ ] %[^ ]", method, path, protocol ) != 3 ) send_error( 400, "Bad Request", (char*) 0, "Can't parse request." ); while ( fgets( line, sizeof(line), stdin ) != (char*) 0 ) { if ( strcmp( line, "\n" ) == 0 || strcmp( line, "\r\n" ) == 0 ) break; } if ( strcasecmp( method, "get" ) != 0 ) send_error( 501, "Not Implemented", (char*) 0, "That method is not implemented." ); if ( path[0] != '/' ) send_error( 400, "Bad Request", (char*) 0, "Bad filename." ); file = &(path[1]); strdecode( file, file ); if ( file[0] == '\0' ) file = "./"; len = strlen( file ); if ( file[0] == '/' || strcmp( file, ".." ) == 0 || strncmp( file, "../", 3 ) == 0 || strstr( file, "/../" ) != (char*) 0 || strcmp( &(file[len-3]), "/.." ) == 0 ) send_error( 400, "Bad Request", (char*) 0, "Illegal filename." ); if ( stat( file, &sb ) < 0 ) send_error( 404, "Not Found", (char*) 0, "File not found." ); //请求路径是文件夹吗 if ( S_ISDIR( sb.st_mode ) ) { if ( file[len-1] != '/' ) { (void) snprintf( location, sizeof(location), "Location: %s/", path ); send_error( 302, "Found", location, "Directories must end with a slash." ); } (void) snprintf( idx, sizeof(idx), "%sindex.html", file ); if ( stat( idx, &sb ) >= 0 ) { file = idx; goto do_file; } //显示请求文件夹下的文件列表 send_headers( 200, "Ok", (char*) 0, "text/html", -1, sb.st_mtime ); (void) printf( "<html><head><title>Index of %s</title></head>\n<body bgcolor=\"#99cc99\"><h4>Index of %s</h4>\n<pre>\n", file, file ); n = scandir( file, &dl, NULL, alphasort ); if ( n < 0 ) perror( "scandir" ); else for ( i = 0; i < n; ++i ) file_details( file, dl[i]->d_name ); (void) printf( "</pre>\n<hr>\n<address><a href=\"%s\">%s</a></address>\n</body></html>\n", SERVER_URL, SERVER_NAME ); } else { //返回请求的文件 do_file: fp = fopen( file, "r" ); if ( fp == (FILE*) 0 ) send_error( 403, "Forbidden", (char*) 0, "File is protected." ); send_headers( 200, "Ok", (char*) 0, get_mime_type( file ), sb.st_size, sb.st_mtime ); while ( ( ich = getc( fp ) ) != EOF ) putchar( ich ); } (void) fflush( stdout ); exit( 0 ); } //输出文件相关属性的详细信息 static void file_details( char* dir, char* name ) { static char encoded_name[1000]; static char path[2000]; struct stat sb; char timestr[16]; strencode( encoded_name, sizeof(encoded_name), name ); (void) snprintf( path, sizeof(path), "%s/%s", dir, name ); if ( lstat( path, &sb ) < 0 ) (void) printf( "<a href=\"%s\">%-32.32s</a> ???\n", encoded_name, name ); else { (void) strftime( timestr, sizeof(timestr), "%d%b%Y %H:%M", localtime( &sb.st_mtime ) ); (void) printf( "<a href=\"%s\">%-32.32s</a> %15s %14lld\n", encoded_name, name, timestr, (int64_t) sb.st_size ); } } //返回出错页面 static void send_error( int status, char* title, char* extra_header, char* text ) { send_headers( status, title, extra_header, "text/html", -1, -1 ); (void) printf( "<html><head><title>%d %s</title></head>\n<body bgcolor=\"#cc9999\"><h4>%d %s</h4>\n", status, title, status, title ); (void) printf( "%s\n", text ); (void) printf( "<hr>\n<address><a href=\"%s\">%s</a></address>\n</body></html>\n", SERVER_URL, SERVER_NAME ); (void) fflush( stdout ); exit( 1 ); } //设置reponse header //状态标题 mime_type 文件最后被修改的时间 static void send_headers( int status, char* title, char* extra_header, char* mime_type, off_t length, time_t mod ) { time_t now; char timebuf[100]; //\015\012 回车换行 (void) printf( "%s %d %s\015\012", PROTOCOL, status, title ); (void) printf( "Server: %s\015\012", SERVER_NAME ); now = time( (time_t*) 0 ); //将时间格式化后存在timebuf中 (void) strftime( timebuf, sizeof(timebuf), RFC1123FMT, gmtime( &now ) ); (void) printf( "Date: %s\015\012", timebuf ); if ( extra_header != (char*) 0 ) (void) printf( "%s\015\012", extra_header ); if ( mime_type != (char*) 0 ) (void) printf( "Content-Type: %s\015\012", mime_type ); if ( length >= 0 ) (void) printf( "Content-Length: %lld\015\012", (int64_t) length ); if ( mod != (time_t) -1 ) { (void) strftime( timebuf, sizeof(timebuf), RFC1123FMT, gmtime( &mod ) ); (void) printf( "Last-Modified: %s\015\012", timebuf ); } (void) printf( "Connection: close\015\012" ); (void) printf( "\015\012" ); } //通过文件名推断文件mime_type static char* get_mime_type( char* name ) { char* dot; dot = strrchr( name, '.' ); if ( dot == (char*) 0 ) return "text/plain; charset=iso-8859-1"; if ( strcmp( dot, ".html" ) == 0 || strcmp( dot, ".htm" ) == 0 ) return "text/html; charset=iso-8859-1"; if ( strcmp( dot, ".jpg" ) == 0 || strcmp( dot, ".jpeg" ) == 0 ) return "image/jpeg"; if ( strcmp( dot, ".gif" ) == 0 ) return "image/gif"; if ( strcmp( dot, ".png" ) == 0 ) return "image/png"; if ( strcmp( dot, ".css" ) == 0 ) return "text/css"; if ( strcmp( dot, ".au" ) == 0 ) return "audio/basic"; if ( strcmp( dot, ".wav" ) == 0 ) return "audio/wav"; if ( strcmp( dot, ".avi" ) == 0 ) return "video/x-msvideo"; if ( strcmp( dot, ".mov" ) == 0 || strcmp( dot, ".qt" ) == 0 ) return "video/quicktime"; if ( strcmp( dot, ".mpeg" ) == 0 || strcmp( dot, ".mpe" ) == 0 ) return "video/mpeg"; if ( strcmp( dot, ".vrml" ) == 0 || strcmp( dot, ".wrl" ) == 0 ) return "model/vrml"; if ( strcmp( dot, ".midi" ) == 0 || strcmp( dot, ".mid" ) == 0 ) return "audio/midi"; if ( strcmp( dot, ".mp3" ) == 0 ) return "audio/mpeg"; if ( strcmp( dot, ".ogg" ) == 0 ) return "application/ogg"; if ( strcmp( dot, ".pac" ) == 0 ) return "application/x-ns-proxy-autoconfig"; return "text/plain; charset=iso-8859-1"; } //用于URL 解码 static void strdecode( char* to, char* from ) { for ( ; *from != '\0'; ++to, ++from ) { if ( from[0] == '%' && isxdigit( from[1] ) && isxdigit( from[2] ) ) { *to = hexit( from[1] ) * 16 + hexit( from[2] ); from += 2; } else *to = *from; } *to = '\0'; } //十六进制转换为十进制数 static int hexit( char c ) { if ( c >= '0' && c <= '9' ) return c - '0'; if ( c >= 'a' && c <= 'f' ) return c - 'a' + 10; if ( c >= 'A' && c <= 'F' ) return c - 'A' + 10; return 0; /* shouldn't happen, we're guarded by isxdigit() */ } //用于文件名编码 static void strencode( char* to, size_t tosize, const char* from ) { int tolen; for ( tolen = 0; *from != '\0' && tolen + 4 < tosize; ++from ) { //ASCII 字符、数字或者 "/_.-~" 中的一个 if ( isalnum(*from) || strchr( "/_.-~", *from ) != (char*) 0 ) { *to = *from; ++to; ++tolen; } else //对特殊字符进行编码问题：什么样的特殊字符需要这样编码？ { (void) sprintf( to, "%%%02x", (int) *from & 0xff ); to += 3; tolen += 3; } } *to = '\0'; } 参考资料 micro_http 下载地址 micro_httpd的安装与配置后记这是我2012年的文章，原来发表在ITeye，现在一并迁移过来 ...