Subversion Repositories SvarDOS

/*

 * pkgnet - pulls SvarDOS packages from the project's online repository

 * Copyright (C) 2021 Mateusz Viste

 *

 * PUBLISHED UNDER THE TERMS OF THE MIT LICENSE

 *

 * COPYRIGHT (C) 2016-2021 MATEUSZ VISTE, ALL RIGHTS RESERVED.

 *

 * Permission is hereby granted, free of charge, to any person obtaining a

 * copy of this software and associated documentation files (the "Software"),

 * to deal in the Software without restriction, including without limitation

 * the rights to use, copy, modify, merge, publish, distribute, sublicense,

 * and/or sell copies of the Software, and to permit persons to whom the

 * Software is furnished to do so, subject to the following conditions:

 *

 * The above copyright notice and this permission notice shall be included in

 * all copies or substantial portions of the Software.

 *

 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR

 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,

 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE

 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER

 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING

 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER

 * DEALINGS IN THE SOFTWARE.

 *

 * http://svardos.osdn.io

 */

#include <stdio.h>

#include <stdlib.h>

#include <string.h>

#include <time.h>

#include "net.h"

#define PVER "20210520"

#define PDATE "2021"

#define HOSTADDR "svardos.osdn.io"

/* returns length of all http headers, or 0 if uncomplete yet */

static unsigned short detecthttpheadersend(const unsigned char *buff) {

  char lastbyteislf = 0;

  unsigned short i;

  for (i = 0; buff[i] != 0; i++) {

    if (buff[i] == '\r') continue; /* ignore CR characters */

    if (buff[i] != '\n') {

      lastbyteislf = 0;

      continue;

    }

    /* cur byte is LF -> if last one was also LF then this is an empty line, meaning headers are over */

    if (lastbyteislf == 0) {

      lastbyteislf = 1;

      continue;

    }

    /* end of headers! return length of headers */

    return(i + 1); /* add 1 to skip the current \n character */

  }

  return(0);

}

static void help(void) {

  puts("pkgnet ver " PVER " -- Copyright (C) " PDATE " Mateusz Viste");

  puts("");

  puts("pkgnet is the SvarDOS package downloader.");

  puts("");

  puts("usage:  pkgnet search <term>");

  puts("        pkgnet pull <package>");

  puts("        pkgnet checkup");

  puts("");

  puts("actions:");

  puts(" search   - asks remote repository for the list of matching packages");

  puts(" pull     - downloads package into current directory");

  puts(" checkup  - lists updates available for your system");

  puts("");

}

/* parses command line arguments and fills outfname and url accordingly

 * returns 0 on success, non-zero otherwise */

static int parseargv(int argc, char * const *argv, char *outfname, char *url) {

  *outfname = 0;

  *url = 0;

  if ((argc == 3) && (strcasecmp(argv[1], "search") == 0)) {

    sprintf(url, "/repo/?a=search&p=%s", argv[2]);

  } else if ((argc == 3) && (strcasecmp(argv[1], "pull") == 0)) {

    if ((strlen(argv[2]) > 8) || (argv[2][0] == 0)) {

      puts("ERROR: package name must be 8 characters maximum");

      return(-1);

    }

    sprintf(url, "/repo/?a=pull&p=%s", argv[2]);

    sprintf(outfname, "%s.zip", argv[2]);

  } else if ((argc == 2) && (strcasecmp(argv[1], "checkup") == 0)) {

    puts("NOT SUPPORTED YET");

    return(-1);

  } else {

    help();

    return(-1);

  }

  return(0);

}

static int htget_headers(unsigned char *buffer, size_t buffersz, struct net_tcpsocket *sock, int *httpcode)  {

  unsigned char *buffptr = buffer;

  unsigned short bufflen = 0;

  int byteread;

  time_t starttime = time(NULL);

  for (;;) {

    byteread = net_recv(sock, buffptr, buffersz - (bufflen + 1)); /* -1 because I will append a NULL terminator */

    if (byteread > 0) { /* got data */

      int hdlen;

      bufflen += byteread;

      buffptr += byteread;

      buffer[bufflen] = 0;

      hdlen = detecthttpheadersend(buffer);

      if (hdlen > 0) { /* full headers - parse http code and continue processing */

        int spc;

        /* find the first space (HTTP/1.1 200 OK) */

        for (spc = 0; spc < 16; spc++) {

          if (buffer[spc] == ' ') break;

          if (buffer[spc] == 0) break;

        }

        if (buffer[spc] != ' ') return(-1);

        *httpcode = atoi((char *)(buffer + spc + 1));

        /* rewind the buffer */

        bufflen -= hdlen;

        memmove(buffer, buffer + hdlen, bufflen);

        return(bufflen); /* move to body processing now */

      }

    } else if (byteread < 0) { /* abort on error */

      return(-2); /* unexpected end of connection (while waiting for all http headers) */

    } else { /* else no data received - look for timeout and release a cpu cycle */

      if (time(NULL) - starttime > 20) return(-3); /* TIMEOUT! */

      _asm int 28h; /* release a CPU cycle */

    }

  }

}

/* fetch http data from ipaddr using url

 * write result to file outfname if not null, or print to stdout otherwise

 * fills bsum with the BSD sum of the data

 * returns the length of data obtained, or neg value on error */

static long htget(const char *ipaddr, const char *url, const char *outfname, unsigned short *bsum) {

  struct net_tcpsocket *sock;

  unsigned char buffer[4096];

  time_t lastactivity, lastprogressoutput = 0;

  int httpcode = -1;

  int byteread;

  long flen = 0, lastflen = 0;

  FILE *fd = NULL;

  sock = net_connect(ipaddr, 80);

  if (sock == NULL) {

    puts("ERROR: failed to connect to " HOSTADDR);

    goto SHITQUIT;

  }

  /* wait for net_connect() to actually connect */

  for (;;) {

    int connstate = net_isconnected(sock);

    if (connstate > 0) break;

    if (connstate < 0) {

      puts("ERROR: connection error");

      goto SHITQUIT;

    }

    _asm int 28h;  /* DOS idle */

  }

  /* socket is connected - send the http request (MUST be HTTP/1.0 because I do not support chunked transfers!) */

  snprintf((char *)buffer, sizeof(buffer), "GET %s HTTP/1.0\r\nHOST: " HOSTADDR "\r\nUSER-AGENT: pkgnet\r\nConnection: close\r\n\r\n", url);

  if (net_send(sock, buffer, strlen((char *)buffer)) != (int)strlen((char *)buffer)) {

    puts("ERROR: failed to send HTTP query to remote server");

    goto SHITQUIT;

  }

  /* receive and process HTTP headers */

  byteread = htget_headers(buffer, sizeof(buffer), sock, &httpcode);

  /* transmission error? */

  if (byteread < 0) {

    printf("ERROR: communication error (%d)", byteread);

    puts("");

    goto SHITQUIT;

  }

  /* open destination file if required and if no server-side error occured */

  if ((httpcode == 200) && (*outfname != 0)) {

    fd = fopen(outfname, "wb");

    if (fd == NULL) {

      printf("ERROR: failed to create file %s", outfname);

      puts("");

      goto SHITQUIT;

    }

  }

  /* read body of the answer */

  lastactivity = time(NULL);

  for (;; byteread = net_recv(sock, buffer, sizeof(buffer) - 1)) { /* read 1 byte less because I need to append a NULL terminator */

    if (byteread > 0) { /* got data */

      buffer[byteread] = 0;

      lastactivity = time(NULL);

      /* if downloading to file, write stuff to disk */

      if (fd != NULL) {

        int i;

        if (fwrite(buffer, 1, byteread, fd) != byteread) {

          printf("ERROR: failed to write data to file %s after %ld bytes", outfname, flen);

          puts("");

          break;

        }

        flen += byteread;

        /* update progress once a sec */

        if (lastprogressoutput != lastactivity) {

          lastprogressoutput = lastactivity;

          printf("%ld KiB (%ld KiB/s)     \r", flen >> 10, (flen >> 10) - (lastflen >> 10)); /* trailing spaces are meant to avoid leaving garbage on screen if speed goes from, say, 1000 KiB/s to 9 KiB/s */

          lastflen = flen;

          fflush(stdout); /* avoid console buffering */

        }

        /* update the bsd sum */

        for (i = 0; i < byteread; i++) {

          /* rotr16 */

          unsigned short bsumlsb = *bsum & 1;

          *bsum >>= 1;

          *bsum |= (bsumlsb << 15);

          *bsum += buffer[i];

        }

      } else { /* otherwise dump to screen */

        printf("%s", buffer);

      }

    } else if (byteread < 0) { /* end of connection */

      break;

    } else { /* check for timeout (byteread == 0) */

      if (time(NULL) - lastactivity > 20) { /* TIMEOUT! */

        puts("ERROR: Timeout while waiting for data");

        goto SHITQUIT;

      }

      /* waiting for packets - release a CPU cycle in the meantime */

      _asm int 28h;

    }

  }

  goto ALLGOOD;

  SHITQUIT:

  flen = -1;

  ALLGOOD:

  if (fd != NULL) fclose(fd);

  net_close(sock);

  return(flen);

}

/* checks if file exists, returns 0 if not, non-zero otherwise */

static int fexists(const char *fname) {

  FILE *fd = fopen(fname, "rb");

  if (fd == NULL) return(0);

  fclose(fd);

  return(1);

}

int main(int argc, char **argv) {

  char ipaddr[64];

  char url[64];

  unsigned short bsum = 0;

  char outfname[16];

  long flen;

  /* parse command line arguments */

  if (parseargv(argc, argv, outfname, url) != 0) return(1);

  /* if outfname requested, make sure that file does not exist yet */

  if (fexists(outfname)) {

    printf("ERROR: file %s already exists", outfname);

    puts("");

    return(1);

  }

  /* init network stack */

  if (net_init() != 0) {

    puts("ERROR: Network subsystem initialization failed");

    return(1);

  }

  puts(""); /* required because watt-32 likes to print out garbage sometimes ("configuring through DHCP...") */

  if (net_dnsresolve(ipaddr, HOSTADDR) != 0) {

    puts("ERROR: DNS resolution failed");

    return(1);

  }

  flen = htget(ipaddr, url, outfname, &bsum);

  if (flen < 1) return(1);

  if (*outfname != 0) {

    /* print bsum, size, filename */

    printf("Downloaded %ld KiB into %s (BSUM: %04X)", flen >> 10, outfname, bsum);

    puts("");

  }

  return(0);

}