From 1f19f808dbcfe1cb02e4806a9f583ae9c657b7e5 Mon Sep 17 00:00:00 2001
From: Antonio Radici <antonio@dyne.org>
Date: Sat, 10 Sep 2016 11:48:50 +0100
Subject: [PATCH] Allow the user to interrupt slow IO operations

---
 imap/command.c    |  3 +++
 mutt_socket.c     | 16 +++++++++++++++-
 mutt_ssl.c        | 13 +++++++++++--
 mutt_ssl_gnutls.c | 14 ++++++++------
 mx.c              |  2 +-
 sendlib.c         | 17 ++++++++++++++++-
 6 files changed, 54 insertions(+), 11 deletions(-)

diff --git a/imap/command.c b/imap/command.c
index 4d34d2426..5177475bd 100644
--- a/imap/command.c
+++ b/imap/command.c
@@ -242,9 +242,12 @@ int imap_exec (IMAP_DATA* idata, const char* cmdstr, int flags)
   if (flags & IMAP_CMD_QUEUE)
     return 0;
 
+  // Allow interruptions, particularly useful if there are network problems.
+  mutt_allow_interrupt (1);
   do
     rc = imap_cmd_step (idata);
   while (rc == IMAP_CMD_CONTINUE);
+  mutt_allow_interrupt (0);
 
   if (rc == IMAP_CMD_NO && (flags & IMAP_CMD_FAIL_OK))
     return -2;
diff --git a/mutt_socket.c b/mutt_socket.c
index a2c489f65..79aa81e8e 100644
--- a/mutt_socket.c
+++ b/mutt_socket.c
@@ -398,12 +398,19 @@ int raw_socket_read (CONNECTION* conn, char* buf, size_t len)
 {
   int rc;
 
+  mutt_allow_interrupt (1);
   if ((rc = read (conn->fd, buf, len)) == -1)
   {
     mutt_error (_("Error talking to %s (%s)"), conn->account.host,
 		strerror (errno));
     mutt_sleep (2);
-  }
+  } else if (errno == EINTR) {
+    rc = -1;
+    mutt_error (_("Error talking to %s (%s)"), conn->account.host,
+               strerror (errno));
+    mutt_sleep (2);
+   }
+  mutt_allow_interrupt (0);
 
   return rc;
 }
@@ -412,12 +419,19 @@ int raw_socket_write (CONNECTION* conn, const char* buf, size_t count)
 {
   int rc;
 
+  mutt_allow_interrupt (1);
   if ((rc = write (conn->fd, buf, count)) == -1)
   {
     mutt_error (_("Error talking to %s (%s)"), conn->account.host,
 		strerror (errno));
     mutt_sleep (2);
+  } else if (errno == EINTR) {
+    rc = -1;
+    mutt_error (_("Error talking to %s (%s)"), conn->account.host,
+               strerror (errno));
+    mutt_sleep (2);
   }
+  mutt_allow_interrupt (0);
 
   return rc;
 }
diff --git a/mutt_ssl.c b/mutt_ssl.c
index 2a9266fd9..d5826acec 100644
--- a/mutt_ssl.c
+++ b/mutt_ssl.c
@@ -303,8 +303,12 @@ static int ssl_socket_read (CONNECTION* conn, char* buf, size_t len)
   int rc;
 
   rc = SSL_read (data->ssl, buf, len);
-  if (rc <= 0)
+  if (rc <= 0 || errno == EINTR)
   {
+    if (errno == EINTR)
+    {
+      rc = -1;
+    }
     data->isopen = 0;
     ssl_err (data, rc);
   }
@@ -318,8 +322,13 @@ static int ssl_socket_write (CONNECTION* conn, const char* buf, size_t len)
   int rc;
 
   rc = SSL_write (data->ssl, buf, len);
-  if (rc <= 0)
+  if (rc <= 0 || errno == EINTR) {
+    if (errno == EINTR)
+    {
+      rc = -1;
+    }
     ssl_err (data, rc);
+  }
 
   return rc;
 }
diff --git a/mutt_ssl_gnutls.c b/mutt_ssl_gnutls.c
index 2084ad04e..4e6a4fd50 100644
--- a/mutt_ssl_gnutls.c
+++ b/mutt_ssl_gnutls.c
@@ -141,14 +141,16 @@ static int tls_socket_read (CONNECTION* conn, char* buf, size_t len)
 
   do {
     ret = gnutls_record_recv (data->state, buf, len);
-    if (ret < 0 && gnutls_error_is_fatal(ret) == 1)
+    if ((ret < 0 &&
+         gnutls_error_is_fatal(ret) == 1) ||
+        ret == GNUTLS_E_INTERRUPTED
+       )
     {
       mutt_error ("tls_socket_read (%s)", gnutls_strerror (ret));
-      mutt_sleep (4);
+      mutt_sleep (2);
       return -1;
     }
-  }
-  while (ret == GNUTLS_E_AGAIN || ret == GNUTLS_E_INTERRUPTED);
+  } while (ret == GNUTLS_E_AGAIN);
 
   return ret;
 }
@@ -171,7 +173,7 @@ static int tls_socket_write (CONNECTION* conn, const char* buf, size_t len)
     ret = gnutls_record_send (data->state, buf + sent, len - sent);
     if (ret < 0)
     {
-      if (gnutls_error_is_fatal(ret) == 1)
+      if (gnutls_error_is_fatal(ret) == 1 || ret == GNUTLS_E_INTERRUPTED)
       {
 	mutt_error ("tls_socket_write (%s)", gnutls_strerror (ret));
 	mutt_sleep (4);
@@ -434,7 +436,7 @@ static int tls_negotiate (CONNECTION * conn)
 
   err = gnutls_handshake(data->state);
 
-  while (err == GNUTLS_E_AGAIN || err == GNUTLS_E_INTERRUPTED)
+  while (err == GNUTLS_E_AGAIN)
   {
     err = gnutls_handshake(data->state);
   }
diff --git a/mx.c b/mx.c
index 414602a60..14149250f 100644
--- a/mx.c
+++ b/mx.c
@@ -1423,7 +1423,7 @@ MESSAGE *mx_open_new_message (CONTEXT *dest, HEADER *hdr, int flags)
 /* check for new mail */
 int mx_check_mailbox (CONTEXT *ctx, int *index_hint)
 {
-  if (!ctx)
+  if (!ctx || ctx->magic == 0)
   {
     dprint (1, (debugfile, "mx_check_mailbox: null or invalid context.\n"));
     return -1;
diff --git a/sendlib.c b/sendlib.c
index 2ebf45544..cbc546a6c 100644
--- a/sendlib.c
+++ b/sendlib.c
@@ -274,6 +274,10 @@ static void encode_base64 (FGETCONV * fc, FILE *fout, int istext)
 
   while ((ch = fgetconv (fc)) != EOF)
   {
+    if (SigInt == 1) {
+      SigInt = 0;
+      return;
+    }
     if (istext && ch == '\n' && ch1 != '\r')
       b64_putc('\r', fout);
     b64_putc(ch, fout);
@@ -287,8 +291,13 @@ static void encode_8bit (FGETCONV *fc, FILE *fout, int istext)
 {
   int ch;
 
-  while ((ch = fgetconv (fc)) != EOF)
+  while ((ch = fgetconv (fc)) != EOF) {
+    if (SigInt == 1) {
+      SigInt = 0;
+      return;
+    }
     fputc (ch, fout);
+  }
 }
 
 
@@ -465,6 +474,7 @@ int mutt_write_mime_body (BODY *a, FILE *f)
   else
     fc = fgetconv_open (fpin, 0, 0, 0);
 
+  mutt_allow_interrupt (1);
   if (a->encoding == ENCQUOTEDPRINTABLE)
     encode_quoted (fc, f, write_as_text_part (a));
   else if (a->encoding == ENCBASE64)
@@ -473,10 +483,15 @@ int mutt_write_mime_body (BODY *a, FILE *f)
     encode_8bit (fc, f, write_as_text_part (a));
   else
     mutt_copy_stream (fpin, f);
+  mutt_allow_interrupt (0);
 
   fgetconv_close (&fc);
   safe_fclose (&fpin);
 
+  if (SigInt == 1) {
+    SigInt = 0;
+    return -1;
+  }
   return (ferror (f) ? -1 : 0);
 }
 
-- 
2.49.0