icuSources/tools/toolutil/flagparser.c

   1 /******************************************************************************
   2  *   Copyright (C) 2009-2012, International Business Machines
   3  *   Corporation and others.  All Rights Reserved.
   4  *******************************************************************************
   5  */
   6
   7 #include "flagparser.h"
   8 #include "filestrm.h"
   9 #include "cstring.h"
  10 #include "cmemory.h"
  11
  12 #define DEFAULT_BUFFER_SIZE 512
  13
  14 static int32_t currentBufferSize = DEFAULT_BUFFER_SIZE;
  15
  16 static int32_t extractFlag(char* buffer, int32_t bufferSize, char* flag, int32_t flagSize, const char ** flagNames, int32_t numOfFlags, UErrorCode *status);
  17 static int32_t getFlagOffset(const char *buffer, int32_t bufferSize);
  18
  19 /*
  20  * Opens the given fileName and reads in the information storing the data in flagBuffer.
  21  */
  22 U_CAPI int32_t U_EXPORT2
  23 parseFlagsFile(const char *fileName, char **flagBuffer, int32_t flagBufferSize, const char ** flagNames, int32_t numOfFlags, UErrorCode *status) {
  24     char* buffer = uprv_malloc(sizeof(char) * currentBufferSize);
  25     char* tmpFlagBuffer = uprv_malloc(sizeof(char) * flagBufferSize);
  26     UBool allocateMoreSpace = FALSE;
  27     int32_t idx, i;
  28     int32_t result = 0;
  29
  30     FileStream *f = T_FileStream_open(fileName, "r");
  31     if (f == NULL) {
  32         *status = U_FILE_ACCESS_ERROR;
  33         return -1;
  34     }
  35
  36     if (buffer == NULL) {
  37         *status = U_MEMORY_ALLOCATION_ERROR;
  38         return -1;
  39     }
  40
  41     do {
  42         if (allocateMoreSpace) {
  43             allocateMoreSpace = FALSE;
  44             currentBufferSize *= 2;
  45             uprv_free(buffer);
  46             buffer = uprv_malloc(sizeof(char) * currentBufferSize);
  47             if (buffer == NULL) {
  48                 uprv_free(tmpFlagBuffer);
  49                 *status = U_MEMORY_ALLOCATION_ERROR;
  50                 return -1;
  51             }
  52         }
  53         for (i = 0; i < numOfFlags;) {
  54             if (T_FileStream_readLine(f, buffer, currentBufferSize) == NULL) {
  55                 /* End of file reached. */
  56                 break;
  57             }
  58             if (buffer[0] == '#') {
  59                 continue;
  60             }
  61
  62             if (uprv_strlen(buffer) == (currentBufferSize - 1) && buffer[currentBufferSize-2] != '\n') {
  63                 /* Allocate more space for buffer if it didnot read the entrire line */
  64                 allocateMoreSpace = TRUE;
  65                 T_FileStream_rewind(f);
  66                 break;
  67             } else {
  68                 idx = extractFlag(buffer, currentBufferSize, tmpFlagBuffer, flagBufferSize, flagNames, numOfFlags, status);
  69                 if (U_FAILURE(*status)) {
  70                     if (*status == U_BUFFER_OVERFLOW_ERROR) {
  71                         result = currentBufferSize;
  72                     } else {
  73                         result = -1;
  74                     }
  75                     break;
  76                 } else {
  77                     if (flagNames != NULL) {
  78                         if (idx >= 0) {
  79                             uprv_strcpy(flagBuffer[idx], tmpFlagBuffer);
  80                         } else {
  81                             /* No match found.  Skip it. */
  82                             continue;
  83                         }
  84                     } else {
  85                         uprv_strcpy(flagBuffer[i++], tmpFlagBuffer);
  86                     }
  87                 }
  88             }
  89         }
  90     } while (allocateMoreSpace && U_SUCCESS(*status));
  91
  92     uprv_free(tmpFlagBuffer);
  93     uprv_free(buffer);
  94
  95     T_FileStream_close(f);
  96
  97     if (U_SUCCESS(*status) && result == 0) {
  98         currentBufferSize = DEFAULT_BUFFER_SIZE;
  99     }
 100
 101     return result;
 102 }
 103
 104
 105 /*
 106  * Extract the setting after the '=' and store it in flag excluding the newline character.
 107  */
 108 static int32_t extractFlag(char* buffer, int32_t bufferSize, char* flag, int32_t flagSize, const char **flagNames, int32_t numOfFlags, UErrorCode *status) {
 109     int32_t i, idx = -1;
 110     char *pBuffer;
 111     int32_t offset=0;
 112     UBool bufferWritten = FALSE;
 113
 114     if (buffer[0] != 0) {
 115         /* Get the offset (i.e. position after the '=') */
 116         offset = getFlagOffset(buffer, bufferSize);
 117         pBuffer = buffer+offset;
 118         for(i = 0;;i++) {
 119             if (i >= flagSize) {
 120                 *status = U_BUFFER_OVERFLOW_ERROR;
 121                 return -1;
 122             }
 123             if (pBuffer[i+1] == 0) {
 124                 /* Indicates a new line character. End here. */
 125                 flag[i] = 0;
 126                 break;
 127             }
 128
 129             flag[i] = pBuffer[i];
 130             if (i == 0) {
 131                 bufferWritten = TRUE;
 132             }
 133         }
 134     }
 135
 136     if (!bufferWritten) {
 137         flag[0] = 0;
 138     }
 139
 140     if (flagNames != NULL && offset>0) {
 141         offset--;  /* Move offset back 1 because of '='*/
 142         for (i = 0; i < numOfFlags; i++) {
 143             if (uprv_strncmp(buffer, flagNames[i], offset) == 0) {
 144                 idx = i;
 145                 break;
 146             }
 147         }
 148     }
 149
 150     return idx;
 151 }
 152
 153 /*
 154  * Get the position after the '=' character.
 155  */
 156 static int32_t getFlagOffset(const char *buffer, int32_t bufferSize) {
 157     int32_t offset = 0;
 158
 159     for (offset = 0; offset < bufferSize;offset++) {
 160         if (buffer[offset] == '=') {
 161             offset++;
 162             break;
 163         }
 164     }
 165
 166     if (offset == bufferSize || (offset - 1) == bufferSize) {
 167         offset = 0;
 168     }
 169
 170     return offset;
 171 }