From 759fd76395eb3c4bc8605fdb656d8431b9ca404d Mon Sep 17 00:00:00 2001
From: Stefan Monnier <monnier@iro.umontreal.ca>
Date: Thu, 9 May 2013 14:30:46 -0400
Subject: [PATCH] * src/doc.c (get_doc_string): Slightly relax the sanity
 checking. * src/lread.c (skip_dyn_eof): New function. (read1): Use it to skip
 the end of a file in response to #@00.

---
 src/ChangeLog |  7 +++++++
 src/doc.c     | 22 ++++++++++++++--------
 src/lread.c   | 21 ++++++++++++++++++++-
 3 files changed, 41 insertions(+), 9 deletions(-)

diff --git a/src/ChangeLog b/src/ChangeLog
index 95b15a0f5a0..f6685824933 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,3 +1,10 @@
+2013-05-09  Stefan Monnier  <monnier@iro.umontreal.ca>
+
+	* lread.c (skip_dyn_eof): New function.
+	(read1): Use it to skip the end of a file in response to #@00.
+
+	* doc.c (get_doc_string): Slightly relax the sanity checking.
+
 2013-05-09  Jan Djärv  <jan.h.d@swipnet.se>
 
 	* nsfns.m: Include IOGraphicsLib.h if Cocoa.
diff --git a/src/doc.c b/src/doc.c
index 7234fb38bf9..770cb1eb646 100644
--- a/src/doc.c
+++ b/src/doc.c
@@ -215,14 +215,20 @@ get_doc_string (Lisp_Object filepos, bool unibyte, bool definition)
   if (CONSP (filepos))
     {
       int test = 1;
-      if (get_doc_string_buffer[offset - test++] != ' ')
-	return Qnil;
-      while (get_doc_string_buffer[offset - test] >= '0'
-	     && get_doc_string_buffer[offset - test] <= '9')
-	test++;
-      if (get_doc_string_buffer[offset - test++] != '@'
-	  || get_doc_string_buffer[offset - test] != '#')
-	return Qnil;
+      /* A dynamic docstring should be either at the very beginning of a "#@
+	 comment" or right after a dynamic docstring delimiter (in case we
+	 pack several such docstrings within the same comment).  */
+      if (get_doc_string_buffer[offset - test] != '\037')
+	{
+	  if (get_doc_string_buffer[offset - test++] != ' ')
+	    return Qnil;
+	  while (get_doc_string_buffer[offset - test] >= '0'
+		 && get_doc_string_buffer[offset - test] <= '9')
+	    test++;
+	  if (get_doc_string_buffer[offset - test++] != '@'
+	      || get_doc_string_buffer[offset - test] != '#')
+	    return Qnil;
+	}
     }
   else
     {
diff --git a/src/lread.c b/src/lread.c
index 272f252cf7b..15821662fc8 100644
--- a/src/lread.c
+++ b/src/lread.c
@@ -378,6 +378,19 @@ skip_dyn_bytes (Lisp_Object readcharfun, ptrdiff_t n)
     }
 }
 
+static void
+skip_dyn_eof (Lisp_Object readcharfun)
+{
+  if (FROM_FILE_P (readcharfun))
+    {
+      block_input ();		/* FIXME: Not sure if it's needed.  */
+      fseek (instream, 0, SEEK_END);
+      unblock_input ();
+    }
+  else
+    while (READCHAR >= 0);
+}
+
 /* Unread the character C in the way appropriate for the stream READCHARFUN.
    If the stream is a user function, call it with the char as argument.  */
 
@@ -2622,7 +2635,7 @@ read1 (Lisp_Object readcharfun, int *pch, bool first_in_list)
       if (c == '@')
 	{
 	  enum { extra = 100 };
-	  ptrdiff_t i, nskip = 0;
+	  ptrdiff_t i, nskip = 0, digits = 0;
 
 	  /* Read a decimal integer.  */
 	  while ((c = READCHAR) >= 0
@@ -2630,8 +2643,14 @@ read1 (Lisp_Object readcharfun, int *pch, bool first_in_list)
 	    {
 	      if ((STRING_BYTES_BOUND - extra) / 10 <= nskip)
 		string_overflow ();
+	      digits++;
 	      nskip *= 10;
 	      nskip += c - '0';
+	      if (digits == 2 && nskip == 0)
+		{ /* We've just seen #@00, which means "skip to end".  */
+		  skip_dyn_eof (readcharfun);
+		  return Qnil;
+		}
 	    }
 	  if (nskip > 0)
 	    /* We can't use UNREAD here, because in the code below we side-step
-- 
2.39.2