c正则的一个应用

psychopath

下面代码是linux下c正则的一个应用。程序可通过代理privoxy->tor下载代理，默认的代理是127.0.0.1:8118。
所以在编译后运行前，请先保证tor正在运行中，否则无法下载到代理。一般情况下一次能下载到2000个左右的代理。

#include <stdio.h>#include <string.h>#include <stdlib.h>#include <sys/types.h>#include <sys/socket.h>#include <netinet/in.h>#include <arpa/inet.h>#include <unistd.h>#include <netdb.h>#include <regex.h>#define NM 10static int proxy_save_count = 0;static int reg_num;static unsigned short through_proxy_port = 8118;static char code[10];static char *through_proxy_ip = "127.0.0.1";static regex_t **pregs;void die(int i, char *message, char *str){  if(str != NULL){      printf(message, str);    exit(i);  }else{    printf(message);    exit(i);  }}int write_all(int sockfd, char *buf, int *len){  int total = 0, bytesleft = *len, n;  while(total < *len) {    n = write(sockfd, buf + total, bytesleft);    if (n == -1)        break;    total += n;    bytesleft -= n;  }  *len = total;  return n == -1 ? -1 : 0;} void to_lower(char *p){  while(*p){    if(isalpha(*p) && isupper(*p))      *p = tolower(*p);    p++;  }}int parse_http_header(int sockfd, long *bytes){  char buf[100], key[30], value[70], ch, *pb = buf;  int n, i = 0, j = 0;    memset(key, 0, sizeof(key));  memset(value, 0, sizeof(value));  while((n = read(sockfd, &ch, 1)) == 1){    if(ch == '\n'){      if(i == 0)        break;      i = 0;    }else if(ch != '\r'){      pb[i++] = ch;    }else{      pb[i] = '\0';      //printf("%s\n", buf);      if(j++ == 0){        if(!strstr(buf, "HTTP/1.") || !strstr(buf, "200")){          printf("%s\n", buf);          return -1;        }      }else{        if(sscanf(buf, "%[^:]: %[^\n]", key, value ) == 2){          to_lower(key);          if(strcmp("content-length", key) == 0){            *bytes = atol(value);          }        }      }    }  }  if(n == -1){    fprintf(stderr, "read() error\n");    return -2;  }  return 0;}int with_content_length(int sockfd, long bytes, char **recv){  char buf[1024];  int n, len = sizeof(buf);  if((*recv = (char *)malloc(bytes+1)) == NULL)    die(-1, "Memory allocation failed!\n", NULL);  memset(*recv, 0, bytes+1);  while((n = read(sockfd, buf, len-1)) > 0){    buf[n] = '\0';    strcat(*recv, buf);  }  if(n == -1){    fprintf(stderr, "read() error\n");    return 1;  }  close(sockfd);  return 0; }int without_content_length(int sockfd, char **recv){  char buf[1024];  int n, len = sizeof(buf);   int i = 0, total = 0;   while((n = read(sockfd, buf, len-1)) > 0){    total += n;    buf[n] = '\0';    if(i++ == 0){      if((*recv = (char *)malloc(total+1)) == NULL)        die(-1, "Memory allocation failed!\n", NULL);      strcpy(*recv, buf);    }else{      if((*recv = (char *)realloc(*recv, total+1)) == NULL)        die(-1, "Memory reallocation failed!\n", NULL);      strcat(*recv, buf);    }  }  if(n == -1){    fprintf(stderr, "read() error\n");    return 1;  }  close(sockfd);  return 0;}int get_http_body(char *send,  char **recv){  int sockfd, n, i = 0, len = strlen(send);    struct sockaddr_in sa;    struct hostent *he;  long bytes = 0;    if((sockfd = socket(AF_INET, SOCK_STREAM, 0)) == -1){    fprintf(stderr, "socket() falied\n");    return 1;  }   sa.sin_family = AF_INET;  sa.sin_addr.s_addr = inet_addr(through_proxy_ip);  sa.sin_port = htons(through_proxy_port);  if(connect(sockfd, (struct sockaddr *)&sa, sizeof(sa)) == -1){    fprintf(stderr, "connect() failed\n");    return 2;  }  if(write_all(sockfd, send, &len) == -1){    fprintf(stderr, "write() error\n");    return 3;  }  if((parse_http_header(sockfd, &bytes)) < 0)    return 4;  if(bytes > 0){    if(with_content_length(sockfd, bytes, recv))      return 5;  }else{    if(without_content_length(sockfd,  recv))      return 6;  }    return 0;}int sub_string(int start, int end, char *src, char **dst){  int i = start, j = 0;  if((*dst = (char *)malloc(sizeof(char)*(end-start+1))) == NULL)    die(-1, "Memory allocation failed!\n", NULL);  while(i < end)    (*dst)[j++] = src[i++];  (*dst)[j] ='\0';     return 0 ;}int get_index(char *p){  int i;    for(i = 0; i < 10; i++){    if(code[i] == *p)      break;   }   return i;}void get_code(char *p){  int i, j;  memset(code, 0, sizeof(code));  for(i = 0; i < 39; i += 4){    j = atoi(p + i + 2);    code[j]= p[i];  } }void print_port(char *port, FILE *fp){  char ptr[11], *ch = NULL, delims[] = "+";  int i;   memset(ptr, 0, sizeof(ptr));  strcpy(ptr, port);          ch = strtok(ptr, delims);  while(ch != NULL){    i = get_index(ch);    if(i < 10)      fprintf(fp, "%d", i);    else      printf("Can't not decode port\n");    ch = strtok(NULL, delims);  }  fprintf(fp, "\n");}int parse_http_body(char *str, FILE *fp, int eflags, int i, int j, int n, int k, int flag){  char *ip = NULL, *port = NULL, ch = *str;  regmatch_t pm[NM];  const size_t nm = NM;  if(n > NM){    while(*str && regexec(pregs[k], str, nm, pm, eflags) == 0){      sub_string(pm[i].rm_so, pm[i].rm_eo, str, &ip);      if(flag){        get_code(ip);        *str = 0;      }else{        proxy_save_count++;        fprintf(fp, "%s\n", ip);         str = &str[pm[j].rm_eo];      }      free(ip);    }    if(flag)      *str = ch;  }else{    while(*str && regexec(pregs[k], str, nm, pm, eflags) == 0){      sub_string(pm[i].rm_so, pm[i].rm_eo, str, &ip);      sub_string(pm[n].rm_so, pm[n].rm_eo, str, &port);      if(flag){        proxy_save_count++;        fprintf(fp, "%s:", ip);        print_port(port, fp);      }else{        proxy_save_count++;        fprintf(fp, "%s:%s\n", ip, port);      }      free(ip);      free(port);      str = &str[pm[j].rm_eo];    }  }   return 0;}int print_proxys(char *url, int *keys, FILE *fp, int eflags){  char host[30], send[512], *data = NULL;  int i, j, n;  memset(host, 0, sizeof(host));  memset(send, 0, sizeof(send));  if(sscanf(url, "http://%[^/]", host) != 1){    printf("Can't not parse url\n");    return 1;  }  sprintf(send, "GET %s HTTP/1.1\r\nHost: %s\r\nUser-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.2.13) Gecko/20101203 Firefox/3.6.13\r\nAccept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8\r\nAccept-Language: en-us,en;q=0.5\r\nAccept-Encoding: deflate\r\nAccept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.7\r\nKeep-Alive: 115\r\nProxy-Connection: keep-alive\r\n\r\n", url, host);   //printf("%s\n", send);  if(get_http_body(send, &data) != 0)    return 2;  if(keys[1] < 0){    if(keys[0] > reg_num-1 || keys[0] < 0)      return 2;    parse_http_body(data, fp, eflags, 0, 2, 11, keys[0], 0);  }else{    if(keys[0] > reg_num-1 || keys[0] < 0 || keys[1] > reg_num-1 || keys[1] < 0)      return 3;     parse_http_body(data, fp, eflags, 0, 1, 11, keys[0], 1);    parse_http_body(data, fp, eflags, 1, 3, 3, keys[1], 1) ;  }  free(data);  return 0;}int compile_regexs(char **regexs, int cflags){  int i;  if((pregs = (regex_t **)malloc(sizeof(regex_t *)*reg_num)) == NULL)    die(-1, "Memory allocation failed!\n", NULL);  for(i = 0; i < reg_num; i++){    if((pregs[i] = (regex_t *)malloc(sizeof(regex_t))) == NULL)      die(-1, "Memory allocation failed!\n", NULL);    if(regcomp(pregs[i], regexs[i], cflags) != 0){      fprintf(stderr, "regcomp() failed\n");      return (i+1);    }  }   return 0;}void free_regs(void){  int i;  for(i = 0; i < reg_num; i++)    regfree(pregs[i]);  free(pregs);}int main(){  char *file = "proxy.txt";  FILE *fp = NULL;  int num, i, keys[2];    int eflags = 0, cflags = REG_EXTENDED|REG_NEWLINE;  if((fp = fopen(file, "w")) == NULL)    die(-1, "Failed to create the file %s\n", file);    char *regexs[] = {"([0-9]{1,3}\\.){3}([0-9]{1,3}:[0-9]{1,5})",                                      "([a-z]=[0-9];){10}",                   "(([0-9]{1,3}\\.){3}[0-9]{1,3})[^\\+]+((\\+[a-z]){1,5})",                   };  reg_num = sizeof(regexs)/sizeof(char *);  if(compile_regexs(regexs, cflags) != 0)    return 1;  char *urls[] = {"http://www.samair.ru/proxy/type-01.htm",                  "http://www.samair.ru/proxy/type-02.htm",                  "http://www.samair.ru/proxy/type-03.htm",                  "http://www.samair.ru/proxy/type-04.htm",                  "http://www.samair.ru/proxy/type-05.htm",                  "http://www.samair.ru/proxy/type-06.htm",                  "http://www.samair.ru/proxy/type-07.htm",                  "http://www.samair.ru/proxy/type-08.htm",                  "http://www.samair.ru/proxy/type-09.htm",                  "http://www.samair.ru/proxy/type-10.htm",                  "http://www.samair.ru/proxy/type-11.htm",                  "http://www.samair.ru/proxy/type-12.htm",                  "http://www.samair.ru/proxy/type-13.htm",                  "http://www.samair.ru/proxy/type-14.htm",                  "http://www.samair.ru/proxy/type-15.htm",                  "http://www.samair.ru/proxy/type-16.htm",                  "http://www.samair.ru/proxy/type-17.htm",                  "http://www.samair.ru/proxy/type-18.htm",                  "http://www.samair.ru/proxy/type-19.htm",                  "http://www.samair.ru/proxy/type-20.htm",                 };  num = sizeof(urls)/sizeof(char *);  printf("Proxy downloading is processing...\n");  for(i = 0; i < num; i++){    if(i < 10){      keys[0] = 1; keys[1] = 2;    }else{      keys[0] = 0; keys[1] = -1;    }       print_proxys(urls[i], keys, fp, eflags);  }  if(proxy_save_count > 0)    printf("Now we have downloaded %d proxys, saved in the file %s\n", proxy_save_count, file);  else    printf("Oops, no proxy saved!\n");  fclose(fp);  free_regs();  return 0;  }
来自http://www.innohot.com/?p=19