Remove gotos in JBig2 code.

core/src/fxcodec/jbig2/JBig2_GsidProc.cpp

 // Copyright 2015 PDFium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
 
 #include "JBig2_GsidProc.h"
 
 #include "../../../../third_party/base/nonstd_unique_ptr.h"
 #include "../../../include/fxcrt/fx_basic.h"
 #include "JBig2_BitStream.h"
 #include "JBig2_GrdProc.h"
 #include "JBig2_Image.h"
 
 FX_DWORD* CJBig2_GSIDProc::decode_Arith(CJBig2_ArithDecoder* pArithDecoder,
                                         JBig2ArithCtx* gbContext,
                                         IFX_Pause* pPause) {
-  CJBig2_Image** GSPLANES;
-  int32_t J, K;
-  FX_DWORD x, y;
-  FX_DWORD* GSVALS;
-  GSPLANES = FX_Alloc(CJBig2_Image*, GSBPP);
-  GSVALS = FX_Alloc2D(FX_DWORD, GSW, GSH);
-  JBIG2_memset(GSPLANES, 0, sizeof(CJBig2_Image*) * GSBPP);
-  JBIG2_memset(GSVALS, 0, sizeof(FX_DWORD) * GSW * GSH);
-
   nonstd::unique_ptr<CJBig2_GRDProc> pGRD(new CJBig2_GRDProc());
   pGRD->MMR = GSMMR;
   pGRD->GBW = GSW;
   pGRD->GBH = GSH;
   pGRD->GBTEMPLATE = GSTEMPLATE;
   pGRD->TPGDON = 0;
   pGRD->USESKIP = GSUSESKIP;
   pGRD->SKIP = GSKIP;
   if (GSTEMPLATE <= 1) {
     pGRD->GBAT[0] = 3;
   } else {
     pGRD->GBAT[0] = 2;
   }
   pGRD->GBAT[1] = -1;
   if (pGRD->GBTEMPLATE == 0) {
     pGRD->GBAT[2] = -3;
     pGRD->GBAT[3] = -1;
     pGRD->GBAT[4] = 2;
     pGRD->GBAT[5] = -2;
     pGRD->GBAT[6] = -2;
     pGRD->GBAT[7] = -2;
   }
+
+  nonstd::unique_ptr<CJBig2_Image*, FxFreeDeleter> GSPLANES(
+      FX_Alloc(CJBig2_Image*, GSBPP));
+  JBIG2_memset(GSPLANES.get(), 0, sizeof(CJBig2_Image*) * GSBPP);
   FXCODEC_STATUS status = pGRD->Start_decode_Arith(
-      &GSPLANES[GSBPP - 1], pArithDecoder, gbContext, nullptr);
+      &GSPLANES.get()[GSBPP - 1], pArithDecoder, gbContext, nullptr);
   while (status == FXCODEC_STATUS_DECODE_TOBECONTINUE) {
     pGRD->Continue_decode(pPause);
   }
-  if (!GSPLANES[GSBPP - 1]) {
-    goto failed;
-  }
-  J = GSBPP - 2;
+  if (!GSPLANES.get()[GSBPP - 1])
+    return nullptr;
+
+  int32_t J = GSBPP - 2;
   while (J >= 0) {
     FXCODEC_STATUS status = pGRD->Start_decode_Arith(
-        &GSPLANES[J], pArithDecoder, gbContext, nullptr);
+        &GSPLANES.get()[J], pArithDecoder, gbContext, nullptr);
     while (status == FXCODEC_STATUS_DECODE_TOBECONTINUE) {
       pGRD->Continue_decode(pPause);
     }
-    if (!GSPLANES[J]) {
-      for (K = GSBPP - 1; K > J; K--) {
-        delete GSPLANES[K];
-        goto failed;
+    if (!GSPLANES.get()[J]) {
+      for (int32_t K = GSBPP - 1; K > J; --K) {
+        delete GSPLANES.get()[K];
+        return nullptr;
       }
     }
-    GSPLANES[J]->composeFrom(0, 0, GSPLANES[J + 1], JBIG2_COMPOSE_XOR);
+    GSPLANES.get()[J]->composeFrom(0, 0, GSPLANES.get()[J + 1],
+                                   JBIG2_COMPOSE_XOR);
     J = J - 1;
   }
-  for (y = 0; y < GSH; y++) {
-    for (x = 0; x < GSW; x++) {
-      for (J = 0; J < GSBPP; J++) {
-        GSVALS[y * GSW + x] |= GSPLANES[J]->getPixel(x, y) << J;
+  nonstd::unique_ptr<FX_DWORD, FxFreeDeleter> GSVALS(
+      FX_Alloc2D(FX_DWORD, GSW, GSH));
+  JBIG2_memset(GSVALS.get(), 0, sizeof(FX_DWORD) * GSW * GSH);
+  for (FX_DWORD y = 0; y < GSH; ++y) {
+    for (FX_DWORD x = 0; x < GSW; ++x) {
+      for (J = 0; J < GSBPP; ++J) {
+        GSVALS.get()[y * GSW + x] |= GSPLANES.get()[J]->getPixel(x, y) << J;
       }
     }
   }
-  for (J = 0; J < GSBPP; J++) {
-    delete GSPLANES[J];
+  for (J = 0; J < GSBPP; ++J) {
+    delete GSPLANES.get()[J];
   }
-  FX_Free(GSPLANES);
-  return GSVALS;
-failed:
-  FX_Free(GSPLANES);
-  FX_Free(GSVALS);
-  return nullptr;
+  return GSVALS.release();
 }
 
 FX_DWORD* CJBig2_GSIDProc::decode_MMR(CJBig2_BitStream* pStream,
                                       IFX_Pause* pPause) {
-  CJBig2_Image** GSPLANES;
-  int32_t J, K;
-  FX_DWORD x, y;
-  FX_DWORD* GSVALS;
-  GSPLANES = FX_Alloc(CJBig2_Image*, GSBPP);
-  GSVALS = FX_Alloc2D(FX_DWORD, GSW, GSH);
-  JBIG2_memset(GSPLANES, 0, sizeof(CJBig2_Image*) * GSBPP);
-  JBIG2_memset(GSVALS, 0, sizeof(FX_DWORD) * GSW * GSH);
-
   nonstd::unique_ptr<CJBig2_GRDProc> pGRD(new CJBig2_GRDProc());
   pGRD->MMR = GSMMR;
   pGRD->GBW = GSW;
   pGRD->GBH = GSH;
+
+  nonstd::unique_ptr<CJBig2_Image*> GSPLANES(FX_Alloc(CJBig2_Image*, GSBPP));
+  JBIG2_memset(GSPLANES.get(), 0, sizeof(CJBig2_Image*) * GSBPP);
   FXCODEC_STATUS status =
-      pGRD->Start_decode_MMR(&GSPLANES[GSBPP - 1], pStream, nullptr);
+      pGRD->Start_decode_MMR(&GSPLANES.get()[GSBPP - 1], pStream, nullptr);
   while (status == FXCODEC_STATUS_DECODE_TOBECONTINUE) {
     pGRD->Continue_decode(pPause);
   }
-  if (!GSPLANES[GSBPP - 1]) {
-    goto failed;
-  }
+  if (!GSPLANES.get()[GSBPP - 1])
+    return nullptr;
+
   pStream->alignByte();
   pStream->offset(3);
-  J = GSBPP - 2;
+  int32_t J = GSBPP - 2;
   while (J >= 0) {
     FXCODEC_STATUS status =
-        pGRD->Start_decode_MMR(&GSPLANES[J], pStream, nullptr);
+        pGRD->Start_decode_MMR(&GSPLANES.get()[J], pStream, nullptr);
     while (status == FXCODEC_STATUS_DECODE_TOBECONTINUE) {
       pGRD->Continue_decode(pPause);
     }
-    if (!GSPLANES[J]) {
-      for (K = GSBPP - 1; K > J; K--) {
-        delete GSPLANES[K];
-        goto failed;
+    if (!GSPLANES.get()[J]) {
+      for (int32_t K = GSBPP - 1; K > J; --K) {
+        delete GSPLANES.get()[K];
+        return nullptr;
       }
     }
     pStream->alignByte();
     pStream->offset(3);
-    GSPLANES[J]->composeFrom(0, 0, GSPLANES[J + 1], JBIG2_COMPOSE_XOR);
+    GSPLANES.get()[J]->composeFrom(0, 0, GSPLANES.get()[J + 1],
+                                   JBIG2_COMPOSE_XOR);
     J = J - 1;
   }
-  for (y = 0; y < GSH; y++) {
-    for (x = 0; x < GSW; x++) {
-      for (J = 0; J < GSBPP; J++) {
-        GSVALS[y * GSW + x] |= GSPLANES[J]->getPixel(x, y) << J;
+  nonstd::unique_ptr<FX_DWORD> GSVALS(FX_Alloc2D(FX_DWORD, GSW, GSH));
+  JBIG2_memset(GSVALS.get(), 0, sizeof(FX_DWORD) * GSW * GSH);
+  for (FX_DWORD y = 0; y < GSH; ++y) {
+    for (FX_DWORD x = 0; x < GSW; ++x) {
+      for (J = 0; J < GSBPP; ++J) {
+        GSVALS.get()[y * GSW + x] |= GSPLANES.get()[J]->getPixel(x, y) << J;
       }
     }
   }
-  for (J = 0; J < GSBPP; J++) {
-    delete GSPLANES[J];
+  for (J = 0; J < GSBPP; ++J) {
+    delete GSPLANES.get()[J];
   }
-  FX_Free(GSPLANES);
-  return GSVALS;
-failed:
-  FX_Free(GSPLANES);
-  FX_Free(GSVALS);
-  return nullptr;
+  return GSVALS.release();
 }