From df4608dd598f2ae22e67e43e49b6f5908c8228b7 Mon Sep 17 00:00:00 2001
From: Michael Ow <mow@svn.icu-project.org>
Date: Tue, 5 Oct 2010 04:52:16 +0000
Subject: [PATCH] ICU-8015 Improve performance of pkgdata tool file parser.

X-SVN-Rev: 28763
---
 icu4c/source/tools/pkgdata/pkgdata.cpp   |  5 +++--
 icu4c/source/tools/toolutil/flagparser.c | 26 ++++++++++++++++++------
 icu4c/source/tools/toolutil/flagparser.h |  4 ++--
 3 files changed, 25 insertions(+), 10 deletions(-)

diff --git a/icu4c/source/tools/pkgdata/pkgdata.cpp b/icu4c/source/tools/pkgdata/pkgdata.cpp
index a0e74830a47..857169bcde4 100644
--- a/icu4c/source/tools/pkgdata/pkgdata.cpp
+++ b/icu4c/source/tools/pkgdata/pkgdata.cpp
@@ -752,6 +752,7 @@ static int32_t initializePkgDataFlags(UPKGOptions *o) {
     UErrorCode status = U_ZERO_ERROR;
     int32_t result = 0;
     int32_t currentBufferSize = SMALL_BUFFER_MAX_SIZE;
+    int32_t tmpResult = 0;
 
     /* Initialize pkgdataFlags */
     pkgDataFlags = (char**)uprv_malloc(sizeof(char*) * PKGDATA_FLAGS_SIZE);
@@ -785,12 +786,12 @@ static int32_t initializePkgDataFlags(UPKGOptions *o) {
           fprintf(stdout, "# Reading options file %s\n", o->options);
         }
         status = U_ZERO_ERROR;
-        parseFlagsFile(o->options, pkgDataFlags, currentBufferSize, (int32_t)PKGDATA_FLAGS_SIZE, &status);
+        tmpResult = parseFlagsFile(o->options, pkgDataFlags, currentBufferSize, (int32_t)PKGDATA_FLAGS_SIZE, &status);
         if (status == U_BUFFER_OVERFLOW_ERROR) {
             for (int32_t i = 0; i < PKGDATA_FLAGS_SIZE; i++) {
                 uprv_free(pkgDataFlags[i]);
             }
-            currentBufferSize *= 2;
+            currentBufferSize = tmpResult;
         } else if (U_FAILURE(status)) {
             fprintf(stderr,"Unable to open or read \"%s\" option file. status = %s\n", o->options, u_errorName(status));
             return -1;
diff --git a/icu4c/source/tools/toolutil/flagparser.c b/icu4c/source/tools/toolutil/flagparser.c
index 507f2cefadb..718a2551602 100644
--- a/icu4c/source/tools/toolutil/flagparser.c
+++ b/icu4c/source/tools/toolutil/flagparser.c
@@ -9,7 +9,9 @@
 #include "cstring.h"
 #include "cmemory.h"
 
-#define BUFFER_DEFAULT_SIZE 512
+#define DEFAULT_BUFFER_SIZE 512
+
+static int32_t currentBufferSize = DEFAULT_BUFFER_SIZE;
 
 static void extractFlag(char* buffer, int32_t bufferSize, char* flag, int32_t flagSize, UErrorCode *status);
 static int32_t getFlagOffset(const char *buffer, int32_t bufferSize);
@@ -17,22 +19,22 @@ static int32_t getFlagOffset(const char *buffer, int32_t bufferSize);
 /*
  * Opens the given fileName and reads in the information storing the data in flagBuffer.
  */
-U_CAPI void U_EXPORT2
+U_CAPI int32_t U_EXPORT2
 parseFlagsFile(const char *fileName, char **flagBuffer, int32_t flagBufferSize, int32_t numOfFlags, UErrorCode *status) {
-    int32_t currentBufferSize = BUFFER_DEFAULT_SIZE;
     char* buffer = uprv_malloc(sizeof(char) * currentBufferSize);
     UBool allocateMoreSpace = FALSE;
     int32_t i;
+    int32_t result = 0;
 
     FileStream *f = T_FileStream_open(fileName, "r");
     if (f == NULL) {
         *status = U_FILE_ACCESS_ERROR;
-        return;
+        return -1;
     }
 
     if (buffer == NULL) {
         *status = U_MEMORY_ALLOCATION_ERROR;
-        return;
+        return -1;
     }
 
     do {
@@ -58,16 +60,28 @@ parseFlagsFile(const char *fileName, char **flagBuffer, int32_t flagBufferSize,
                 T_FileStream_rewind(f);
                 break;
             } else {
-
                 extractFlag(buffer, currentBufferSize, flagBuffer[i], flagBufferSize, status);
                 if (U_FAILURE(*status)) {
+                    if (*status == U_BUFFER_OVERFLOW_ERROR) {
+                        result = currentBufferSize;
+                    } else {
+                        result = -1;
+                    }
                     break;
                 }
             }
         }
     } while (allocateMoreSpace && U_SUCCESS(*status));
 
+    uprv_free(buffer);
+
     T_FileStream_close(f);
+
+    if (U_SUCCESS(*status) && result == 0) {
+        currentBufferSize = DEFAULT_BUFFER_SIZE;
+    }
+
+    return result;
 }
 
 
diff --git a/icu4c/source/tools/toolutil/flagparser.h b/icu4c/source/tools/toolutil/flagparser.h
index e31c7cfc3db..64056ed7a79 100644
--- a/icu4c/source/tools/toolutil/flagparser.h
+++ b/icu4c/source/tools/toolutil/flagparser.h
@@ -1,7 +1,7 @@
 /*
 *******************************************************************************
 *
-*   Copyright (C) 2009, International Business Machines
+*   Copyright (C) 2009-2010, International Business Machines
 *   Corporation and others.  All Rights Reserved.
 *
 *******************************************************************************
@@ -24,7 +24,7 @@
 
 #include "unicode/utypes.h"
 
-U_CAPI void U_EXPORT2
+U_CAPI int32_t U_EXPORT2
 parseFlagsFile(const char *fileName, char **flagBuffer, int32_t flagBufferSize, int32_t numOfFlags, UErrorCode *status);
 
 #endif