pop.c

mutt-1.5.12 源代码。linux 下邮件接受的工具。

/*
 * Copyright (C) 2000-2002 Vsevolod Volkov <[e-mail]>
 * Copyright (C) 2006 Rocco Rutte <[e-mail]>
 * 
 *     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, write to the Free Software
 *     Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 */ 

#if HAVE_CONFIG_H
# include "config.h"
#endif

#include "mutt.h"
#include "mutt_curses.h"
#include "mx.h"
#include "pop.h"
#include "mutt_crypt.h"
#include "bcache.h"
#if USE_HCACHE
#include "hcache.h"
#endif

#include <string.h>
#include <unistd.h>

/* write line to file */
static int fetch_message (char *line, void *file)
{
  FILE *f = (FILE *) file;

  fputs (line, f);
  if (fputc ('\n', f) == EOF)
    return -1;

  return 0;
}

/*
 * Read header
 * returns:
 *  0 on success
 * -1 - conection lost,
 * -2 - invalid command or execution error,
 * -3 - error writing to tempfile
 */
static int pop_read_header (POP_DATA *pop_data, HEADER *h)
{
  FILE *f;
  int ret, index;
  long length;
  char buf[LONG_STRING];
  char tempfile[_POSIX_PATH_MAX];

  mutt_mktemp (tempfile);
  if (!(f = safe_fopen (tempfile, "w+")))
  {
    mutt_perror (tempfile);
    return -3;
  }

  snprintf (buf, sizeof (buf), "LIST %d\r\n", h->refno);
  ret = pop_query (pop_data, buf, sizeof (buf));
  if (ret == 0)
  {
    sscanf (buf, "+OK %d %ld", &index, &length);

    snprintf (buf, sizeof (buf), "TOP %d 0\r\n", h->refno);
    ret = pop_fetch_data (pop_data, buf, NULL, fetch_message, f);

    if (pop_data->cmd_top == 2)
    {
      if (ret == 0)
      {
	pop_data->cmd_top = 1;

	dprint (1, (debugfile, "pop_read_header: set TOP capability\n"));
      }

      if (ret == -2)
      {
	pop_data->cmd_top = 0;

	dprint (1, (debugfile, "pop_read_header: unset TOP capability\n"));
	snprintf (pop_data->err_msg, sizeof (pop_data->err_msg),
		_("Command TOP is not supported by server."));
      }
    }
  }

  switch (ret)
  {
    case 0:
    {
      rewind (f);
      h->env = mutt_read_rfc822_header (f, h, 0, 0);
      h->content->length = length - h->content->offset + 1;
      rewind (f);
      while (!feof (f))
      {
	h->content->length--;
	fgets (buf, sizeof (buf), f);
      }
      break;
    }
    case -2:
    {
      mutt_error ("%s", pop_data->err_msg);
      break;
    }
    case -3:
    {
      mutt_error _("Can't write header to temporary file!");
      break;
    }
  }

  fclose (f);
  unlink (tempfile);
  return ret;
}

/* parse UIDL */
static int fetch_uidl (char *line, void *data)
{
  int i, index;
  CONTEXT *ctx = (CONTEXT *)data;
  POP_DATA *pop_data = (POP_DATA *)ctx->data;

  sscanf (line, "%d %s", &index, line);
  for (i = 0; i < ctx->msgcount; i++)
    if (!mutt_strcmp (line, ctx->hdrs[i]->data))
      break;

  if (i == ctx->msgcount)
  {
    dprint (1, (debugfile, "pop_fetch_headers: new header %d %s\n", index, line));

    if (i >= ctx->hdrmax)
      mx_alloc_memory(ctx);

    ctx->msgcount++;
    ctx->hdrs[i] = mutt_new_header ();
    ctx->hdrs[i]->data = safe_strdup (line);
  }
  else if (ctx->hdrs[i]->index != index - 1)
    pop_data->clear_cache = 1;

  ctx->hdrs[i]->refno = index;
  ctx->hdrs[i]->index = index - 1;

  return 0;
}

static int msg_cache_check (const char *id, body_cache_t *bcache, void *data)
{
  CONTEXT *ctx;
  POP_DATA *pop_data;
  int i;

  if (!(ctx = (CONTEXT *)data))
    return -1;
  if (!(pop_data = (POP_DATA *)ctx->data))
    return -1;

  for (i = 0; i < ctx->msgcount; i++)
    /* if the id we get is known for a header: done (i.e. keep in cache) */
    if (ctx->hdrs[i]->data && mutt_strcmp (ctx->hdrs[i]->data, id) == 0)
      return 0;

  /* message not found in context -> remove it from cache
   * return the result of bcache, so we stop upon its first error
   */
  return mutt_bcache_del (bcache, id);
}

/*
 * Read headers
 * returns:
 *  0 on success
 * -1 - conection lost,
 * -2 - invalid command or execution error,
 * -3 - error writing to tempfile
 */
static int pop_fetch_headers (CONTEXT *ctx)
{
  int i, ret, old_count, new_count;
  unsigned short hcached = 0, bcached;
  POP_DATA *pop_data = (POP_DATA *)ctx->data;

#ifdef USE_HCACHE
  header_cache_t *hc = NULL;
  void *data;

  hc = mutt_hcache_open (HeaderCache, ctx->path);
#endif

  time (&pop_data->check_time);
  pop_data->clear_cache = 0;

  for (i = 0; i < ctx->msgcount; i++)
    ctx->hdrs[i]->refno = -1;

  old_count = ctx->msgcount;
  ret = pop_fetch_data (pop_data, "UIDL\r\n", NULL, fetch_uidl, ctx);
  new_count = ctx->msgcount;
  ctx->msgcount = old_count;

  if (pop_data->cmd_uidl == 2)
  {
    if (ret == 0)
    {
      pop_data->cmd_uidl = 1;

      dprint (1, (debugfile, "pop_fetch_headers: set UIDL capability\n"));
    }

    if (ret == -2 && pop_data->cmd_uidl == 2)
    {
      pop_data->cmd_uidl = 0;

      dprint (1, (debugfile, "pop_fetch_headers: unset UIDL capability\n"));
      snprintf (pop_data->err_msg, sizeof (pop_data->err_msg),
	      _("Command UIDL is not supported by server."));
    }
  }

  if (ret == 0)
  {
    for (i = 0; i < old_count; i++)
      if (ctx->hdrs[i]->refno == -1)
	ctx->hdrs[i]->deleted = 1;

    for (i = old_count; i < new_count; i++)
    {
      mutt_message (_("Fetching message headers... [%d/%d]"),
		    i + 1 - old_count, new_count - old_count);

#if USE_HCACHE
      if ((data = mutt_hcache_fetch (hc, ctx->hdrs[i]->data, strlen)))
      {
	char *uidl = safe_strdup (ctx->hdrs[i]->data);
	int refno = ctx->hdrs[i]->refno;
	int index = ctx->hdrs[i]->index;
	/*
	 * - POP dynamically numbers headers and relies on h->refno
	 *   to map messages; so restore header and overwrite restored
	 *   refno with current refno, same for index
	 * - h->data needs to a separate pointer as it's driver-specific
	 *   data freed separately elsewhere
	 *   (the old h->data should point inside a malloc'd block from
	 *   hcache so there shouldn't be a memleak here)
	 */
	HEADER *h = mutt_hcache_restore ((unsigned char *) data, NULL);
	mutt_free_header (&ctx->hdrs[i]);
	ctx->hdrs[i] = h;
	ctx->hdrs[i]->refno = refno;
	ctx->hdrs[i]->index = index;
	ctx->hdrs[i]->data = uidl;
	ret = 0;
	hcached = 1;
      }
      else
#endif
      if ((ret = pop_read_header (pop_data, ctx->hdrs[i])) < 0)
	break;
#if USE_HCACHE
      else
      {
	mutt_hcache_store (hc, ctx->hdrs[i]->data, ctx->hdrs[i], 0, strlen);
      }

      FREE(&data);
#endif

      /*
       * faked support for flags works like this:
       * - if 'hcached' is 1, we have the message in our hcache:
       *        - if we also have a body: read
       *        - if we don't have a body: old
       *          (if $mark_old is set which is maybe wrong as
       *          $mark_old should be considered for syncing the
       *          folder and not when opening it XXX)
       * - if 'hcached' is 0, we don't have the message in our hcache:
       *        - if we also have a body: read
       *        - if we don't have a body: new
       */
      bcached = mutt_bcache_exists (pop_data->bcache, ctx->hdrs[i]->data) == 0;
      ctx->hdrs[i]->old = 0;
      ctx->hdrs[i]->read = 0;
      if (hcached)
      {
        if (bcached)
          ctx->hdrs[i]->read = 1;
        else if (option (OPTMARKOLD))
          ctx->hdrs[i]->old = 1;
      }
      else
      {
        if (bcached)
          ctx->hdrs[i]->read = 1;
      }

      ctx->msgcount++;
    }

    if (i > old_count)
      mx_update_context (ctx, i - old_count);
  }

#if USE_HCACHE
    mutt_hcache_close (hc);
#endif

  if (ret < 0)
  {
    for (i = ctx->msgcount; i < new_count; i++)
      mutt_free_header (&ctx->hdrs[i]);
    return ret;
  }

  /* after putting the result into our structures,
   * clean up cache, i.e. wipe messages deleted outside
   * the availability of our cache
   */
  mutt_bcache_list (pop_data->bcache, msg_cache_check, (void*)ctx);

  mutt_clear_error ();
  return (new_count - old_count);
}

/* open POP mailbox - fetch only headers */
int pop_open_mailbox (CONTEXT *ctx)
{
  int ret;
  char buf[LONG_STRING];
  CONNECTION *conn;
  ACCOUNT acct;
  POP_DATA *pop_data;
  ciss_url_t url;

  if (pop_parse_path (ctx->path, &acct))
  {
    mutt_error (_("%s is an invalid POP path"), ctx->path);
    mutt_sleep (2);
    return -1;
  }

  mutt_account_tourl (&acct, &url);
  url.path = NULL;
  url_ciss_tostring (&url, buf, sizeof (buf), 0);
  conn = mutt_conn_find (NULL, &acct);
  if (!conn)
    return -1;

  FREE (&ctx->path);
  ctx->path = safe_strdup (buf);

  pop_data = safe_calloc (1, sizeof (POP_DATA));
  pop_data->conn = conn;
  ctx->data = pop_data;

  if (pop_open_connection (pop_data) < 0)
    return -1;

  conn->data = pop_data;
  pop_data->bcache = mutt_bcache_open (&acct, NULL);

  FOREVER
  {
    if (pop_reconnect (ctx) < 0)
      return -1;

    ctx->size = pop_data->size;

    mutt_message _("Fetching list of messages...");

    ret = pop_fetch_headers (ctx);

    if (ret >= 0)
      return 0;

    if (ret < -1)
    {
      mutt_sleep (2);
      return -1;
    }
  }
}

/* delete all cached messages */
static void pop_clear_cache (POP_DATA *pop_data)
{
  int i;

  if (!pop_data->clear_cache)
    return;

  dprint (1, (debugfile, "pop_clear_cache: delete cached messages\n"));

  for (i = 0; i < POP_CACHE_LEN; i++)
  {
    if (pop_data->cache[i].path)
    {
      unlink (pop_data->cache[i].path);
      FREE (&pop_data->cache[i].path);
    }
  }
}

/* close POP mailbox */
void pop_close_mailbox (CONTEXT *ctx)