Remove almost all usages of CFX_FixedBufGrow from cpdf_dibsource.cpp

This CL removes all the usages of CFX_FixedBufGrow, except for one that would
cause performance issues for our corpus tests.

Bug: pdfium:177
Change-Id: I0ad76c14f713b116cf7dce50606554e3b03d9f2c
Reviewed-on: https://pdfium-review.googlesource.com/35150
Commit-Queue: Nicolás Peña Moreno <npm@chromium.org>
Reviewed-by: dsinclair <dsinclair@chromium.org>

1 files changed, 10 insertions, 11 deletions

diff --git a/core/fpdfapi/render/cpdf_dibsource.cpp b/core/fpdfapi/render/cpdf_dibsource.cpp
index d1eba2e467..98a2dda999 100644
--- a/core/fpdfapi/render/cpdf_dibsource.cpp
+++ b/core/fpdfapi/render/cpdf_dibsource.cpp
@@ -763,15 +763,15 @@ void CPDF_DIBSource::LoadPalette() {
   }
 
   int palette_count = 1 << (m_bpc * m_nComponents);
-  CFX_FixedBufGrow<float, 16> color_values(m_nComponents);
-  float* color_value = color_values;
+  // Using at least 16 elements due to the call m_pColorSpace->GetRGB().
+  std::vector<float> color_values(std::max(m_nComponents, 16u));
   for (int i = 0; i < palette_count; i++) {
     int color_data = i;
     for (uint32_t j = 0; j < m_nComponents; j++) {
       int encoded_component = color_data % (1 << m_bpc);
       color_data /= 1 << m_bpc;
-      color_value[j] = m_CompData[j].m_DecodeMin +
-                       m_CompData[j].m_DecodeStep * encoded_component;
+      color_values[j] = m_CompData[j].m_DecodeMin +
+                        m_CompData[j].m_DecodeStep * encoded_component;
     }
     float R = 0;
     float G = 0;
@@ -780,12 +780,11 @@ void CPDF_DIBSource::LoadPalette() {
         m_pColorSpace->CountComponents() > 1) {
       int nComponents = m_pColorSpace->CountComponents();
       std::vector<float> temp_buf(nComponents);
-      for (int k = 0; k < nComponents; k++) {
-        temp_buf[k] = *color_value;
-      }
+      for (int k = 0; k < nComponents; ++k)
+        temp_buf[k] = color_values[0];
       m_pColorSpace->GetRGB(temp_buf.data(), &R, &G, &B);
     } else {
-      m_pColorSpace->GetRGB(color_value, &R, &G, &B);
+      m_pColorSpace->GetRGB(color_values.data(), &R, &G, &B);
     }
     SetPaletteArgb(i, ArgbEncode(255, FXSYS_round(R * 255),
                                  FXSYS_round(G * 255), FXSYS_round(B * 255)));
@@ -833,8 +832,8 @@ void CPDF_DIBSource::TranslateScanline24bpp(uint8_t* dest_scan,
   if (TranslateScanline24bppDefaultDecode(dest_scan, src_scan))
     return;
 
-  CFX_FixedBufGrow<float, 16> color_values1(m_nComponents);
-  float* color_values = color_values1;
+  // Using at least 16 elements due to the call m_pColorSpace->GetRGB().
+  std::vector<float> color_values(std::max(m_nComponents, 16u));
   float R = 0.0f;
   float G = 0.0f;
   float B = 0.0f;
@@ -862,7 +861,7 @@ void CPDF_DIBSource::TranslateScanline24bpp(uint8_t* dest_scan,
       G = (1.0f - color_values[1]) * k;
       B = (1.0f - color_values[2]) * k;
     } else if (m_Family != PDFCS_PATTERN) {
-      m_pColorSpace->GetRGB(color_values, &R, &G, &B);
+      m_pColorSpace->GetRGB(color_values.data(), &R, &G, &B);
     }
     R = pdfium::clamp(R, 0.0f, 1.0f);
     G = pdfium::clamp(G, 0.0f, 1.0f);