path: root/lib/libalpm/dload.c

/*
 *  download.c
 *
 *  Copyright (c) 2002-2008 by Judd Vinet <jvinet@zeroflux.org>
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

#include "config.h"

#include <stdlib.h>
#include <stdio.h>
#include <errno.h>
#include <string.h>
#include <unistd.h>
#include <download.h> /* libdownload */

/* libalpm */
#include "dload.h"
#include "alpm_list.h"
#include "alpm.h"
#include "log.h"
#include "util.h"
#include "error.h"
#include "handle.h"

/* Return a 'struct url' for this server, for downloading 'filename'. */
static struct url *url_for_file(const char *url, const char *filename)
{
  struct url *ret = NULL;
  char *buf = NULL;
  int len;

  /* print url + filename into a buffer */
  len = strlen(url) + strlen(filename) + 2;
  CALLOC(buf, len, sizeof(char), RET_ERR(PM_ERR_MEMORY, NULL));
  snprintf(buf, len, "%s/%s", url, filename);

  ret = downloadParseURL(buf);
  FREE(buf);
  if(!ret) {
    _alpm_log(PM_LOG_ERROR, _("url '%s' is invalid\n"), buf);
    RET_ERR(PM_ERR_SERVER_BAD_URL, NULL);
  }

  /* if no URL scheme specified, assume HTTP */
  if(strlen(ret->scheme) == 0) {
    _alpm_log(PM_LOG_WARNING, _("url scheme not specified, assuming HTTP\n"));
    strcpy(ret->scheme, SCHEME_HTTP);
  }
  /* add a user & password for anonymous FTP */
  if(strcmp(ret->scheme,SCHEME_FTP) == 0 && strlen(ret->user) == 0) {
    strcpy(ret->user, "anonymous");
    strcpy(ret->pwd, "libalpm@guest");
  }

  return(ret);
}

/* TODO temporary private declaration */
int _alpm_downloadfiles_forreal(alpm_list_t *servers, const char *localpath,
  alpm_list_t *files, time_t mtime1, time_t *mtime2);


/* TODO implement these as real functions */
int _alpm_download_single_file(const char *filename,
    alpm_list_t *servers, const char *localpath,
    time_t mtimeold, time_t *mtimenew)
{
  alpm_list_t *files = NULL;
  int ret;

  /* make a temp one element list */
  files = alpm_list_add(files, (char*)filename);

  ret = _alpm_downloadfiles_forreal(servers, localpath,
      files, mtimeold, mtimenew);

  /* free list (data was NOT duplicated) */
  alpm_list_free(files);
  return(ret);
}

int _alpm_download_files(alpm_list_t *files,
    alpm_list_t *servers, const char *localpath)
{
  int ret;

  ret = _alpm_downloadfiles_forreal(servers, localpath,
      files, 0, NULL);

  return(ret);
}


/*
 * This is the real downloadfiles, used directly by sync_synctree() to check
 * modtimes on remote files.
 *   - if mtime1 is non-NULL, then only download files if they are different
 *     than mtime1.
 *   - if *mtime2 is non-NULL, it will be filled with the mtime of the remote
 *     file.
 *
 * RETURN:  0 for successful download
 *          1 if the mtimes are identical
 *         -1 on error
 */
int _alpm_downloadfiles_forreal(alpm_list_t *servers, const char *localpath,
  alpm_list_t *files, time_t mtime1, time_t *mtime2)
{
  int dl_thisfile = 0;
  alpm_list_t *lp;
  alpm_list_t *complete = NULL;
  alpm_list_t *i;
  int ret = -1;
  char *pkgname = NULL;

  ALPM_LOG_FUNC;

  if(files == NULL) {
    return(0);
  }

  for(i = servers; i; i = i->next) {
    const char *server = i->data;

    /* get each file in the list */
    for(lp = files; lp; lp = lp->next) {
      struct url *fileurl = NULL;
      char realfile[PATH_MAX];
      char output[PATH_MAX];
      char *fn = (char *)lp->data;

      fileurl = url_for_file(server, fn);
      if(!fileurl) {
        goto cleanup;
      }

      /* pass the raw filename for passing to the callback function */
      FREE(pkgname);
      STRDUP(pkgname, fn, (void)0);
      _alpm_log(PM_LOG_DEBUG, "using '%s' for download progress\n", pkgname);

      snprintf(realfile, PATH_MAX, "%s%s", localpath, fn);
      snprintf(output, PATH_MAX, "%s%s.part", localpath, fn);

      if(alpm_list_find_str(complete, fn)) {
        continue;
      }

      if(!handle->xfercommand
          || !strcmp(fileurl->scheme, "file")) {
        FILE *dlf, *localf = NULL;
        struct url_stat ust;
        struct stat st;
        int chk_resume = 0;

        if(stat(output, &st) == 0 && st.st_size > 0) {
          _alpm_log(PM_LOG_DEBUG, "existing file found, using it\n");
          fileurl->offset = (off_t)st.st_size;
          dl_thisfile = st.st_size;
          localf = fopen(output, "a");
          chk_resume = 1;
        } else {
          fileurl->offset = (off_t)0;
          dl_thisfile = 0;
        }

        /* libdownload does not reset the error code, reset it in
         * the case of previous errors */
        downloadLastErrCode = 0;

        /* 10s timeout - TODO make a config option */
        downloadTimeout = 10000;

        dlf = downloadXGet(fileurl, &ust, (handle->nopassiveftp ? "" : "p"));

        if(downloadLastErrCode != 0 || dlf == NULL) {
          const char *host = _("disk");
          if(strcmp(SCHEME_FILE, fileurl->scheme) != 0) {
            host = fileurl->host;
          }
          _alpm_log(PM_LOG_ERROR, _("failed retrieving file '%s' from %s : %s\n"),
                    fn, host, downloadLastErrString);
          if(localf != NULL) {
            fclose(localf);
          }
          /* try the next server */
          downloadFreeURL(fileurl);
          continue;
        } else {
            _alpm_log(PM_LOG_DEBUG, "connected to %s successfully\n", fileurl->host);
        }

        if(ust.mtime && mtime1 && ust.mtime == mtime1) {
          _alpm_log(PM_LOG_DEBUG, "mtimes are identical, skipping %s\n", fn);
          complete = alpm_list_add(complete, fn);
          if(localf != NULL) {
            fclose(localf);
          }
          if(dlf != NULL) {
            fclose(dlf);
          }
          downloadFreeURL(fileurl);
          ret = 1;
          goto cleanup;
        }

        if(ust.mtime && mtime2) {
          *mtime2 = ust.mtime;
        }

        if(chk_resume && fileurl->offset == 0) {
          _alpm_log(PM_LOG_WARNING, _("cannot resume download, starting over\n"));
          if(localf != NULL) {
            fclose(localf);
            localf = NULL;
          }
        }

        if(localf == NULL) {
          _alpm_rmrf(output);
          fileurl->offset = (off_t)0;
          dl_thisfile = 0;
          localf = fopen(output, "w");
          if(localf == NULL) { /* still null? */
            _alpm_log(PM_LOG_ERROR, _("cannot write to file '%s'\n"), output);
            if(dlf != NULL) {
              fclose(dlf);
            }
            downloadFreeURL(fileurl);
            goto cleanup;
          }
        }

        /* Progress 0 - initialize */
        if(handle->dlcb) {
          handle->dlcb(pkgname, 0, ust.size);
        }

        int nread = 0;
        char buffer[PM_DLBUF_LEN];
        while((nread = fread(buffer, 1, PM_DLBUF_LEN, dlf)) > 0) {
          if(ferror(dlf)) {
            _alpm_log(PM_LOG_ERROR, _("error downloading '%s': %s\n"),
                      fn, downloadLastErrString);
            fclose(localf);
            fclose(dlf);
            downloadFreeURL(fileurl);
            goto cleanup;
          }

          int nwritten = 0;
          while(nwritten < nread) {
            nwritten += fwrite(buffer, 1, (nread - nwritten), localf);
            if(ferror(localf)) {
              _alpm_log(PM_LOG_ERROR, _("error writing to file '%s': %s\n"),
                        realfile, strerror(errno));
              fclose(localf);
              fclose(dlf);
              downloadFreeURL(fileurl);
              goto cleanup;
            }
          }

          if(nwritten != nread) {

          }
          dl_thisfile += nread;

          if(handle->dlcb) {
            handle->dlcb(pkgname, dl_thisfile, ust.size);
          }
        }

        downloadFreeURL(fileurl);
        fclose(localf);
        fclose(dlf);
        rename(output, realfile);
        complete = alpm_list_add(complete, fn);
      } else {
        int ret;
        int usepart = 0;
        char *ptr1, *ptr2;
        char origCmd[PATH_MAX];
        char parsedCmd[PATH_MAX] = "";
        char url[PATH_MAX];
        char cwd[PATH_MAX];

        /* build the full download url */
        snprintf(url, PATH_MAX, "%s://%s%s", fileurl->scheme,
            fileurl->host, fileurl->doc);
        /* we don't need this anymore */
        downloadFreeURL(fileurl);

        /* replace all occurrences of %o with fn.part */
        strncpy(origCmd, handle->xfercommand, sizeof(origCmd));
        ptr1 = origCmd;
        while((ptr2 = strstr(ptr1, "%o"))) {
          usepart = 1;
          ptr2[0] = '\0';
          strcat(parsedCmd, ptr1);
          strcat(parsedCmd, output);
          ptr1 = ptr2 + 2;
        }
        strcat(parsedCmd, ptr1);
        /* replace all occurrences of %u with the download URL */
        strncpy(origCmd, parsedCmd, sizeof(origCmd));
        parsedCmd[0] = '\0';
        ptr1 = origCmd;
        while((ptr2 = strstr(ptr1, "%u"))) {
          ptr2[0] = '\0';
          strcat(parsedCmd, ptr1);
          strcat(parsedCmd, url);
          ptr1 = ptr2 + 2;
        }
        strcat(parsedCmd, ptr1);
        /* cwd to the download directory */
        getcwd(cwd, PATH_MAX);
        if(chdir(localpath)) {
          _alpm_log(PM_LOG_WARNING, _("could not chdir to %s\n"), localpath);
          pm_errno = PM_ERR_CONNECT_FAILED;
          goto cleanup;
        }
        /* execute the parsed command via /bin/sh -c */
        _alpm_log(PM_LOG_DEBUG, "running command: %s\n", parsedCmd);
        ret = system(parsedCmd);
        if(ret == -1) {
          _alpm_log(PM_LOG_WARNING, _("running XferCommand: fork failed!\n"));
          pm_errno = PM_ERR_FORK_FAILED;
          goto cleanup;
        } else if(ret != 0) {
          /* download failed */
          _alpm_log(PM_LOG_DEBUG, "XferCommand command returned non-zero status code (%d)\n", ret);
        } else {
          /* download was successful */
          complete = alpm_list_add(complete, fn);
          if(usepart) {
            rename(output, realfile);
          }
        }
        chdir(cwd);
      }
    }

    if(alpm_list_count(complete) == alpm_list_count(files)) {
      ret = 0;
      goto cleanup;
    }
  }

cleanup:
  FREE(pkgname);
  alpm_list_free(complete);

  return(ret);
}

/** Fetch a remote pkg.
 * @param url URL of the package to download
 * @return the downloaded filepath on success, NULL on error
 * @addtogroup alpm_misc
 */
char SYMEXPORT *alpm_fetch_pkgurl(const char *url)
{
  /* TODO this method will not work at all right now */
  char *filename, *filepath;
  const char *cachedir;

  ALPM_LOG_FUNC;

  filename = NULL;

  /* find a valid cache dir to download to */
  cachedir = _alpm_filecache_setup();

  /* download the file */
  if(_alpm_download_single_file(NULL, NULL, cachedir, 0, NULL)) {
    _alpm_log(PM_LOG_WARNING, _("failed to download %s\n"), url);
    return(NULL);
  }
  _alpm_log(PM_LOG_DEBUG, "successfully downloaded %s\n", url);

  /* we should be able to find the file the second time around */
  filepath = _alpm_filecache_find(filename);
  return(filepath);
}

/* vim: set ts=2 sw=2 noet: */