From e004b5893e21cbd251553a3de06955b95baf2728 Mon Sep 17 00:00:00 2001
From: anders_k <anders_k@212acab6-be3b-0410-9dea-997c60f758d6>
Date: Tue, 25 Apr 2017 13:58:43 +0000
Subject: [PATCH] Use a internal command to detect the CHM header because the
 !searchparse hack fails with a encoding error if the ACP codepage is 936.

git-svn-id: https://svn.code.sf.net/p/nsis/code/NSIS/trunk@6853 212acab6-be3b-0410-9dea-997c60f758d6
---
 Examples/makensis.nsi |  2 +-
 Source/build.cpp      | 26 ++++++++++++++++++++------
 Source/script.cpp     |  3 +--
 3 files changed, 22 insertions(+), 9 deletions(-)

diff --git a/Examples/makensis.nsi b/Examples/makensis.nsi
index 3a47f449..904fdfe2 100644
--- a/Examples/makensis.nsi
+++ b/Examples/makensis.nsi
@@ -161,7 +161,7 @@ ${MementoSection} "NSIS Core Files (required)" SecCore
   File ..\makensisw.exe
   File ..\COPYING
   File ..\NSIS.chm
-  !searchparse /file "..\NSIS.chm" "ITSF" VALIDATE_CHM
+  !pragma verifychm "..\NSIS.chm"
   File ..\NSIS.exe
   !if /FileExists "..\NSIS.exe.manifest"
     File "..\NSIS.exe.manifest"
diff --git a/Source/build.cpp b/Source/build.cpp
index 0855d5a7..5ca55213 100644
--- a/Source/build.cpp
+++ b/Source/build.cpp
@@ -30,6 +30,7 @@
 #include "crc32.h"
 #include "manifest.h"
 #include "icon.h"
+#include "utf.h" // For NStream
 
 #include "exehead/api.h"
 #include "exehead/resource.h"
@@ -3408,18 +3409,31 @@ void CEXEBuild::set_verbosity(int lvl)
 
 int CEXEBuild::parse_pragma(LineParser &line)
 {
-  if (line.gettoken_enum(1, _T("warning\0")) == -1)
-    return (warning_fl(DW_PP_PRAGMA_UNKNOWN, _T("Unknown pragma")), PS_ERROR);
+  const int rvSucc = PS_OK, rvWarn = PS_WARNING, rvErr = PS_WARNING; // rvErr is not PS_ERROR because we want !pragma parsing to be very forgiving.
 
-  int warnOp = line.gettoken_enum(2, _T("disable\0enable\0default\0push\0pop\0")), ret = PS_OK;
+  // 2.47 shipped with a corrupted CHM file (bug #1129). This minimal verification command exists because the !searchparse hack we added does not work with codepage 936!
+  if (line.gettoken_enum(1, _T("verifychm\0")) == 0)
+  {
+    struct { UINT32 Sig, Ver, cbH; } chm;
+    NIStream f;
+    bool valid = f.OpenFileForReading(line.gettoken_str(2));
+    valid = valid && 12 == f.ReadOctets(&chm, 12);
+    valid = valid && FIX_ENDIAN_INT32(chm.Sig) == 0x46535449 && (FIX_ENDIAN_INT32(chm.Ver)|1) == 3; // 'ITSF' v2..3
+    return valid ? rvSucc : (ERROR_MSG(_T("Invalid format\n")), PS_ERROR);
+  }
+
+  if (line.gettoken_enum(1, _T("warning\0")) == -1)
+    return (warning_fl(DW_PP_PRAGMA_UNKNOWN, _T("Unknown pragma")), rvErr);
+
+  int warnOp = line.gettoken_enum(2, _T("disable\0enable\0default\0push\0pop\0")), ret = rvSucc;
   if (warnOp < 0)
-    ret = PS_ERROR, warning_fl(DW_PP_PRAGMA_UNKNOWN, _T("Unknown pragma")); // Unknown warning pragma action
+    ret = rvErr, warning_fl(DW_PP_PRAGMA_UNKNOWN, _T("Unknown pragma")); // Unknown warning pragma action
   else if (warnOp == 3)
     diagstate.Push();
   else if (warnOp == 4)
   {
     if (!diagstate.Pop())
-      ret = PS_WARNING, warning_fl(DW_PP_PRAGMA_INVALID, _T("Unexpected"));
+      ret = rvWarn, warning_fl(DW_PP_PRAGMA_INVALID, _T("Unexpected"));
   }
   else // warning: disable/enable/default
   {
@@ -3427,7 +3441,7 @@ int CEXEBuild::parse_pragma(LineParser &line)
     {
       DIAGCODE code = static_cast<DIAGCODE>(line.gettoken_int(ti));
       if (!diagstate.IsValidCode(code))
-        ret = PS_WARNING, warning_fl(DW_PP_PRAGMA_INVALID, _T("Invalid number: \"%") NPRIs _T("\""), line.gettoken_str(ti));
+        ret = rvWarn, warning_fl(DW_PP_PRAGMA_INVALID, _T("Invalid number: \"%") NPRIs _T("\""), line.gettoken_str(ti));
       else if (warnOp == 0)
         diagstate.Disable(code);
       else // if ((warnOp == 1) | (warnOp == 2)) All warnings currently default to enabled
diff --git a/Source/script.cpp b/Source/script.cpp
index d361afa8..e524f4c0 100644
--- a/Source/script.cpp
+++ b/Source/script.cpp
@@ -3367,8 +3367,7 @@ int CEXEBuild::doCommand(int which_token, LineParser &line)
       }
     return PS_OK;
     case TOK_P_PRAGMA:
-      parse_pragma(line); // Never abort with ERROR_MSG, even if the pragma is unknown/invalid
-    return PS_OK;
+    return parse_pragma(line) == PS_ERROR ? PS_ERROR : PS_OK;
     case TOK_P_ERROR:
       ERROR_MSG(_T("!error: %") NPRIs _T("\n"),line.gettoken_str(1));
     return PS_ERROR;