allow relooper to manager its own output buffer, to avoid fixed output limits1.8.7

5 files changed, 138 insertions, 15 deletions

diff --git a/src/relooper/Relooper.cpp b/src/relooper/Relooper.cpp
index 389d7447..1bad872f 100644
--- a/src/relooper/Relooper.cpp
+++ b/src/relooper/Relooper.cpp
@@ -40,27 +40,56 @@ static void PutIndented(const char *String);
 static char *OutputBufferRoot = NULL;
 static char *OutputBuffer = NULL;
 static int OutputBufferSize = 0;
+static int OutputBufferOwned = false;
+
+static int LeftInOutputBuffer() {
+  return OutputBufferSize - (OutputBuffer - OutputBufferRoot);
+}
+
+static bool EnsureOutputBuffer(int Needed) { // ensures the output buffer is sufficient. returns true is no problem happened
+  Needed++; // ensure the trailing \0 is not forgotten
+  int Left = LeftInOutputBuffer();
+  if (!OutputBufferOwned) {
+    assert(Needed < Left);
+  } else {
+    // we own the buffer, and can resize if necessary
+    if (Needed >= Left) {
+      int Offset = OutputBuffer - OutputBufferRoot;
+      int TotalNeeded = OutputBufferSize + Needed - Left + 10240;
+      int NewSize = OutputBufferSize;
+      while (NewSize < TotalNeeded) NewSize = NewSize + (NewSize/2);
+      //printf("resize %d => %d\n", OutputBufferSize, NewSize);
+      OutputBufferRoot = (char*)realloc(OutputBufferRoot, NewSize);
+      OutputBuffer = OutputBufferRoot + Offset;
+      OutputBufferSize = NewSize;
+      return false;
+    }
+  }
+  return true;
+}
 
 void PrintIndented(const char *Format, ...) {
   assert(OutputBuffer);
-  assert(OutputBuffer + Indenter::CurrIndent*INDENTATION - OutputBufferRoot < OutputBufferSize);
+  EnsureOutputBuffer(Indenter::CurrIndent*INDENTATION);
   for (int i = 0; i < Indenter::CurrIndent*INDENTATION; i++, OutputBuffer++) *OutputBuffer = ' ';
-  va_list Args;
-  va_start(Args, Format);
-  int left = OutputBufferSize - (OutputBuffer - OutputBufferRoot);
-  int written = vsnprintf(OutputBuffer, left, Format, Args);
-  assert(written < left);
-  OutputBuffer += written;
-  va_end(Args);
+  int Written;
+  while (1) { // write and potentially resize buffer until we have enough room
+    int Left = LeftInOutputBuffer();
+    va_list Args;
+    va_start(Args, Format);
+    Written = vsnprintf(OutputBuffer, Left, Format, Args);
+    va_end(Args);
+    if (EnsureOutputBuffer(Written)) break;
+  }
+  OutputBuffer += Written;
 }
 
 void PutIndented(const char *String) {
   assert(OutputBuffer);
-  assert(OutputBuffer + Indenter::CurrIndent*INDENTATION - OutputBufferRoot < OutputBufferSize);
+  EnsureOutputBuffer(Indenter::CurrIndent*INDENTATION);
   for (int i = 0; i < Indenter::CurrIndent*INDENTATION; i++, OutputBuffer++) *OutputBuffer = ' ';
-  int left = OutputBufferSize - (OutputBuffer - OutputBufferRoot);
-  int needed = strlen(String)+1;
-  assert(needed < left);
+  int Needed = strlen(String)+1;
+  EnsureOutputBuffer(Needed);
   strcpy(OutputBuffer, String);
   OutputBuffer += strlen(String);
   *OutputBuffer++ = '\n';
@@ -1158,11 +1187,17 @@ void Relooper::Render() {
 void Relooper::SetOutputBuffer(char *Buffer, int Size) {
   OutputBufferRoot = OutputBuffer = Buffer;
   OutputBufferSize = Size;
+  OutputBufferOwned = false;
 }
 
 void Relooper::MakeOutputBuffer(int Size) {
   OutputBufferRoot = OutputBuffer = (char*)malloc(Size);
   OutputBufferSize = Size;
+  OutputBufferOwned = true;
+}
+
+char *Relooper::GetOutputBuffer() {
+  return OutputBufferRoot;
 }
 
 void Relooper::SetAsmJSMode(int On) {
diff --git a/src/relooper/Relooper.h b/src/relooper/Relooper.h
index dfabcabb..6b9394db 100644
--- a/src/relooper/Relooper.h
+++ b/src/relooper/Relooper.h
@@ -200,11 +200,16 @@ struct Relooper {
   void Render();
 
   // Sets the global buffer all printing goes to. Must call this or MakeOutputBuffer.
+  // XXX: this is deprecated, see MakeOutputBuffer
   static void SetOutputBuffer(char *Buffer, int Size);
 
-  // Creates an output buffer. Must call this or SetOutputBuffer.
+  // Creates an internal output buffer. Must call this or SetOutputBuffer. Size is
+  // a hint for the initial size of the buffer, it can be resized later one demand.
+  // For that reason this is more recommended than SetOutputBuffer.
   static void MakeOutputBuffer(int Size);
 
+  static char *GetOutputBuffer();
+
   // Sets asm.js mode on or off (default is off)
   static void SetAsmJSMode(int On);
 
diff --git a/src/relooper/fuzzer.py b/src/relooper/fuzzer.py
index fa47583e..18db997e 100644
--- a/src/relooper/fuzzer.py
+++ b/src/relooper/fuzzer.py
@@ -47,8 +47,18 @@ while(1) switch(label) {
 
 int main() {
   char *buffer = (char*)malloc(10*1024*1024);
+'''
+
+  if random.randint(0, 1) == 0:
+    make = False
+    fast += '''
   Relooper::SetOutputBuffer(buffer, 10*1024*1024);
 '''
+  else:
+    make = True
+    fast += '''
+  Relooper::MakeOutputBuffer(%d);
+''' % random.randint(1, 1024*1024*10)
 
   for i in range(1, num):
     slow += '  case %d: print(%d); state = check(); modded = state %% %d\n' % (i, i, len(branches[i])+1)
@@ -102,11 +112,11 @@ int main() {
   printf("\\n\\n");
   r.Render();
 
-  puts(buffer);
+  puts(%s);
 
   return 1;
 }
-'''
+''' % ('buffer' if not make else 'Relooper::GetOutputBuffer()')
 
   slow += '}'
 
diff --git a/src/relooper/test.cpp b/src/relooper/test.cpp
index 773f6ee4..b4ce669c 100644
--- a/src/relooper/test.cpp
+++ b/src/relooper/test.cpp
@@ -286,5 +286,33 @@ int main() {
 
     puts(buffer);
   }
+
+  if (1) {
+    Relooper::MakeOutputBuffer(10);
+
+    printf("\n\n-- If pattern, emulated, using MakeOutputBuffer --\n\n");
+
+    Block *b_a = new Block("// block A\n", NULL);
+    Block *b_b = new Block("// block B\n", "b_check()");
+    Block *b_c = new Block("// block C\n", NULL);
+
+    b_a->AddBranchTo(b_b, "check == 10", "atob();");
+    b_a->AddBranchTo(b_c, NULL, "atoc();");
+
+    b_b->AddBranchTo(b_c, "case 17:", "btoc();");
+    b_b->AddBranchTo(b_a, NULL, NULL);
+
+    Relooper r;
+    r.SetEmulate(true);
+    r.AddBlock(b_a);
+    r.AddBlock(b_b);
+    r.AddBlock(b_c);
+
+    r.Calculate(b_a);
+    printf("\n\n", "the_var");
+    r.Render();
+
+    puts(buffer);
+  }
 }
 
diff --git a/src/relooper/test.txt b/src/relooper/test.txt
index 9bdd4093..cb02b867 100644
--- a/src/relooper/test.txt
+++ b/src/relooper/test.txt
@@ -315,3 +315,48 @@
   }
  }
 
+
+
+-- If pattern, emulated, using MakeOutputBuffer --
+
+
+
+ label = 1;
+ L0:  while(1) {
+  switch(label|0) {
+   case 3: {
+    // block C
+    break;
+   }
+   case 1: {
+    // block A
+    if (check == 10) {
+     atob();
+     label = 2;
+     continue L0;
+    } else {
+     atoc();
+     label = 3;
+     continue L0;
+    }
+    break;
+   }
+   case 2: {
+    // block B
+    switch (b_check()) {
+    case 17: {
+     btoc();
+     label = 3;
+     continue L0;
+     break;
+    }
+    default: {
+     label = 1;
+     continue L0;
+    }
+    }
+    break;
+   }
+  }
+ }
+