klib/kopen.c
2012-01-15 22:51:07 -05:00

344 lines
8.9 KiB
C

#include <stdio.h>
#include <fcntl.h>
#include <errno.h>
#include <ctype.h>
#include <unistd.h>
#include <string.h>
#include <stdlib.h>
#include <signal.h>
#include <sys/types.h>
#ifndef _WIN32
#include <netdb.h>
#include <arpa/inet.h>
#include <sys/socket.h>
#endif
#ifdef _WIN32
#define _KO_NO_NET
#endif
#ifndef _KO_NO_NET
static int socket_wait(int fd, int is_read)
{
fd_set fds, *fdr = 0, *fdw = 0;
struct timeval tv;
int ret;
tv.tv_sec = 5; tv.tv_usec = 0; // 5 seconds time out
FD_ZERO(&fds);
FD_SET(fd, &fds);
if (is_read) fdr = &fds;
else fdw = &fds;
ret = select(fd+1, fdr, fdw, 0, &tv);
if (ret == -1) perror("select");
return ret;
}
static int socket_connect(const char *host, const char *port)
{
#define __err_connect(func) do { perror(func); freeaddrinfo(res); return -1; } while (0)
int on = 1, fd;
struct linger lng = { 0, 0 };
struct addrinfo hints, *res = 0;
memset(&hints, 0, sizeof(struct addrinfo));
hints.ai_family = AF_UNSPEC;
hints.ai_socktype = SOCK_STREAM;
if (getaddrinfo(host, port, &hints, &res) != 0) __err_connect("getaddrinfo");
if ((fd = socket(res->ai_family, res->ai_socktype, res->ai_protocol)) == -1) __err_connect("socket");
if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) == -1) __err_connect("setsockopt");
if (setsockopt(fd, SOL_SOCKET, SO_LINGER, &lng, sizeof(lng)) == -1) __err_connect("setsockopt");
if (connect(fd, res->ai_addr, res->ai_addrlen) != 0) __err_connect("connect");
freeaddrinfo(res);
return fd;
#undef __err_connect
}
static int http_open(const char *fn)
{
char *p, *proxy, *q, *http_host, *host, *port, *path, *buf;
int fd, ret, l;
/* parse URL; adapted from khttp_parse_url() in knetfile.c */
if (strstr(fn, "http://") != fn) return 0;
// set ->http_host
for (p = (char*)fn + 7; *p && *p != '/'; ++p);
l = p - fn - 7;
http_host = calloc(l + 1, 1);
strncpy(http_host, fn + 7, l);
http_host[l] = 0;
for (q = http_host; *q && *q != ':'; ++q);
if (*q == ':') *q++ = 0;
// get http_proxy
proxy = getenv("http_proxy");
// set host, port and path
if (proxy == 0) {
host = strdup(http_host); // when there is no proxy, server name is identical to http_host name.
port = strdup(*q? q : "80");
path = strdup(*p? p : "/");
} else {
host = (strstr(proxy, "http://") == proxy)? strdup(proxy + 7) : strdup(proxy);
for (q = host; *q && *q != ':'; ++q);
if (*q == ':') *q++ = 0;
port = strdup(*q? q : "80");
path = strdup(fn);
}
/* connect; adapted from khttp_connect() in knetfile.c */
l = 0;
fd = socket_connect(host, port);
buf = calloc(0x10000, 1); // FIXME: I am lazy... But in principle, 64KB should be large enough.
l += sprintf(buf + l, "GET %s HTTP/1.0\r\nHost: %s\r\n", path, http_host);
l += sprintf(buf + l, "\r\n");
write(fd, buf, l);
l = 0;
while (read(fd, buf + l, 1)) { // read HTTP header; FIXME: bad efficiency
if (buf[l] == '\n' && l >= 3)
if (strncmp(buf + l - 3, "\r\n\r\n", 4) == 0) break;
++l;
}
buf[l] = 0;
if (l < 14) { // prematured header
close(fd);
fd = -1;
}
ret = strtol(buf + 8, &p, 0); // HTTP return code
if (ret != 200) {
close(fd);
fd = -1;
}
free(buf); free(http_host); free(host); free(port); free(path);
return fd;
}
typedef struct {
int max_response, ctrl_fd;
char *response;
} ftpaux_t;
static int kftp_get_response(ftpaux_t *aux)
{
unsigned char c;
int n = 0;
char *p;
if (socket_wait(aux->ctrl_fd, 1) <= 0) return 0;
while (read(aux->ctrl_fd, &c, 1)) { // FIXME: this is *VERY BAD* for unbuffered I/O
if (n >= aux->max_response) {
aux->max_response = aux->max_response? aux->max_response<<1 : 256;
aux->response = realloc(aux->response, aux->max_response);
}
aux->response[n++] = c;
if (c == '\n') {
if (n >= 4 && isdigit(aux->response[0]) && isdigit(aux->response[1]) && isdigit(aux->response[2])
&& aux->response[3] != '-') break;
n = 0;
continue;
}
}
if (n < 2) return -1;
aux->response[n-2] = 0;
return strtol(aux->response, &p, 0);
}
static int kftp_send_cmd(ftpaux_t *aux, const char *cmd, int is_get)
{
if (socket_wait(aux->ctrl_fd, 0) <= 0) return -1; // socket is not ready for writing
write(aux->ctrl_fd, cmd, strlen(cmd));
return is_get? kftp_get_response(aux) : 0;
}
static int ftp_open(const char *fn)
{
char *p, *host = 0, *port = 0, *retr = 0;
char host2[80], port2[10];
int v[6], l, fd = -1, ret, pasv_port, pasv_ip[4];
ftpaux_t aux;
/* parse URL */
if (strstr(fn, "ftp://") != fn) return 0;
for (p = (char*)fn + 6; *p && *p != '/'; ++p);
if (*p != '/') return 0;
l = p - fn - 6;
port = strdup("21");
host = calloc(l + 1, 1);
strncpy(host, fn + 6, l);
retr = calloc(strlen(p) + 8, 1);
sprintf(retr, "RETR %s\r\n", p);
/* connect to ctrl */
memset(&aux, 0, sizeof(ftpaux_t));
aux.ctrl_fd = socket_connect(host, port);
if (aux.ctrl_fd == -1) goto ftp_open_end; /* fail to connect ctrl */
/* connect to the data stream */
kftp_get_response(&aux);
kftp_send_cmd(&aux, "USER anonymous\r\n", 1);
kftp_send_cmd(&aux, "PASS kopen@\r\n", 1);
kftp_send_cmd(&aux, "TYPE I\r\n", 1);
kftp_send_cmd(&aux, "PASV\r\n", 1);
for (p = aux.response; *p && *p != '('; ++p);
if (*p != '(') goto ftp_open_end;
++p;
sscanf(p, "%d,%d,%d,%d,%d,%d", &v[0], &v[1], &v[2], &v[3], &v[4], &v[5]);
memcpy(pasv_ip, v, 4 * sizeof(int));
pasv_port = (v[4]<<8&0xff00) + v[5];
kftp_send_cmd(&aux, retr, 0);
sprintf(host2, "%d.%d.%d.%d", pasv_ip[0], pasv_ip[1], pasv_ip[2], pasv_ip[3]);
sprintf(port2, "%d", pasv_port);
fd = socket_connect(host2, port2);
if (fd == -1) goto ftp_open_end;
ret = kftp_get_response(&aux);
if (ret != 150) {
close(fd);
fd = -1;
}
close(aux.ctrl_fd);
ftp_open_end:
free(host); free(port); free(retr); free(aux.response);
return fd;
}
#endif /* !defined(_KO_NO_NET) */
static char **cmd2argv(const char *cmd)
{
int i, beg, end, argc;
char **argv, *p, *q, *str;
end = strlen(cmd);
for (i = end - 1; i >= 0; --i)
if (!isspace(cmd[i])) break;
end = i + 1;
for (beg = 0; beg < end; ++beg)
if (!isspace(cmd[beg])) break;
if (beg == end) return 0;
for (i = beg + 1, argc = 0; i < end; ++i)
if (isspace(cmd[i]) && !isspace(cmd[i-1]))
++argc;
argv = (char**)calloc(argc + 2, sizeof(void*));
argv[0] = str = (char*)calloc(end - beg + 1, 1);
strncpy(argv[0], cmd + beg, end - beg);
for (i = argc = 1, q = p = str; i < end - beg; ++i)
if (isspace(str[i])) str[i] = 0;
else if (str[i] && str[i-1] == 0) argv[argc++] = &str[i];
return argv;
}
#define KO_STDIN 1
#define KO_FILE 2
#define KO_PIPE 3
#define KO_HTTP 4
#define KO_FTP 5
typedef struct {
int type, fd;
pid_t pid;
} koaux_t;
void *kopen(const char *fn, int *_fd)
{
koaux_t *aux = 0;
*_fd = -1;
if (strstr(fn, "http://") == fn) {
aux = calloc(1, sizeof(koaux_t));
aux->type = KO_HTTP;
aux->fd = http_open(fn);
} else if (strstr(fn, "ftp://") == fn) {
aux = calloc(1, sizeof(koaux_t));
aux->type = KO_FTP;
aux->fd = ftp_open(fn);
} else if (strcmp(fn, "-") == 0) {
aux = calloc(1, sizeof(koaux_t));
aux->type = KO_STDIN;
aux->fd = STDIN_FILENO;
} else {
const char *p, *q;
for (p = fn; *p; ++p)
if (!isspace(*p)) break;
if (*p == '<') { // pipe open
int need_shell, pfd[2];
pid_t pid;
// a simple check to see if we need to invoke a shell; not always working
for (q = p + 1; *q; ++q)
if (ispunct(*q) && *q != '.' && *q != '_' && *q != '-' && *q != ':')
break;
need_shell = (*q != 0);
pipe(pfd);
pid = vfork();
if (pid == -1) { /* vfork() error */
close(pfd[0]); close(pfd[1]);
return 0;
}
if (pid == 0) { /* the child process */
char **argv; /* FIXME: I do not know if this will lead to a memory leak */
close(pfd[0]);
dup2(pfd[1], STDOUT_FILENO);
close(pfd[1]);
if (!need_shell) {
argv = cmd2argv(p + 1);
execvp(argv[0], argv);
free(argv[0]); free(argv);
} else execl("/bin/sh", "sh", "-c", p + 1, NULL);
exit(1);
} else { /* parent process */
close(pfd[1]);
aux = calloc(1, sizeof(koaux_t));
aux->type = KO_PIPE;
aux->fd = pfd[0];
aux->pid = pid;
}
} else {
#ifdef _WIN32
*_fd = open(fn, O_RDONLY | O_BINARY);
#else
*_fd = open(fn, O_RDONLY);
#endif
if (*_fd) {
aux = calloc(1, sizeof(koaux_t));
aux->type = KO_FILE;
aux->fd = *_fd;
}
}
}
*_fd = aux->fd;
return aux;
}
int kclose(void *a)
{
koaux_t *aux = (koaux_t*)a;
if (aux->type == KO_PIPE) {
int status;
pid_t pid;
pid = waitpid(aux->pid, &status, WNOHANG);
if (pid != aux->pid) kill(aux->pid, 15);
}
return 0;
}
#ifdef _KO_MAIN
#define BUF_SIZE 0x10000
int main(int argc, char *argv[])
{
void *x;
int l, fd;
unsigned char buf[BUF_SIZE];
FILE *fp;
if (argc == 1) {
fprintf(stderr, "Usage: kopen <file>\n");
return 1;
}
x = kopen(argv[1], &fd);
fp = fdopen(fd, "r");
if (fp == 0) {
fprintf(stderr, "ERROR: fail to open the input\n");
return 1;
}
do {
if ((l = fread(buf, 1, BUF_SIZE, fp)) != 0)
fwrite(buf, 1, l, stdout);
} while (l == BUF_SIZE);
fclose(fp);
kclose(x);
return 0;
}
#endif