michael@0: /******************************************************************************
michael@0:  *   Copyright (C) 2009-2012, International Business Machines
michael@0:  *   Corporation and others.  All Rights Reserved.
michael@0:  *******************************************************************************
michael@0:  */
michael@0: 
michael@0: #include "flagparser.h"
michael@0: #include "filestrm.h"
michael@0: #include "cstring.h"
michael@0: #include "cmemory.h"
michael@0: 
michael@0: #define DEFAULT_BUFFER_SIZE 512
michael@0: 
michael@0: static int32_t currentBufferSize = DEFAULT_BUFFER_SIZE;
michael@0: 
michael@0: static int32_t extractFlag(char* buffer, int32_t bufferSize, char* flag, int32_t flagSize, const char ** flagNames, int32_t numOfFlags, UErrorCode *status);
michael@0: static int32_t getFlagOffset(const char *buffer, int32_t bufferSize);
michael@0: 
michael@0: /*
michael@0:  * Opens the given fileName and reads in the information storing the data in flagBuffer.
michael@0:  */
michael@0: U_CAPI int32_t U_EXPORT2
michael@0: parseFlagsFile(const char *fileName, char **flagBuffer, int32_t flagBufferSize, const char ** flagNames, int32_t numOfFlags, UErrorCode *status) {
michael@0:     char* buffer = uprv_malloc(sizeof(char) * currentBufferSize);
michael@0:     char* tmpFlagBuffer = uprv_malloc(sizeof(char) * flagBufferSize);
michael@0:     UBool allocateMoreSpace = FALSE;
michael@0:     int32_t idx, i;
michael@0:     int32_t result = 0;
michael@0: 
michael@0:     FileStream *f = T_FileStream_open(fileName, "r");
michael@0:     if (f == NULL) {
michael@0:         *status = U_FILE_ACCESS_ERROR;
michael@0:         return -1;
michael@0:     }
michael@0: 
michael@0:     if (buffer == NULL) {
michael@0:         *status = U_MEMORY_ALLOCATION_ERROR;
michael@0:         return -1;
michael@0:     }
michael@0: 
michael@0:     do {
michael@0:         if (allocateMoreSpace) {
michael@0:             allocateMoreSpace = FALSE;
michael@0:             currentBufferSize *= 2;
michael@0:             uprv_free(buffer);
michael@0:             buffer = uprv_malloc(sizeof(char) * currentBufferSize);
michael@0:             if (buffer == NULL) {
michael@0:                 uprv_free(tmpFlagBuffer);
michael@0:                 *status = U_MEMORY_ALLOCATION_ERROR;
michael@0:                 return -1;
michael@0:             }
michael@0:         }
michael@0:         for (i = 0; i < numOfFlags;) {
michael@0:             if (T_FileStream_readLine(f, buffer, currentBufferSize) == NULL) {
michael@0:                 /* End of file reached. */
michael@0:                 break;
michael@0:             }
michael@0:             if (buffer[0] == '#') {
michael@0:                 continue;
michael@0:             }
michael@0: 
michael@0:             if (uprv_strlen(buffer) == (currentBufferSize - 1) && buffer[currentBufferSize-2] != '\n') {
michael@0:                 /* Allocate more space for buffer if it didnot read the entrire line */
michael@0:                 allocateMoreSpace = TRUE;
michael@0:                 T_FileStream_rewind(f);
michael@0:                 break;
michael@0:             } else {
michael@0:                 idx = extractFlag(buffer, currentBufferSize, tmpFlagBuffer, flagBufferSize, flagNames, numOfFlags, status);
michael@0:                 if (U_FAILURE(*status)) {
michael@0:                     if (*status == U_BUFFER_OVERFLOW_ERROR) {
michael@0:                         result = currentBufferSize;
michael@0:                     } else {
michael@0:                         result = -1;
michael@0:                     }
michael@0:                     break;
michael@0:                 } else {
michael@0:                     if (flagNames != NULL) {
michael@0:                         if (idx >= 0) {
michael@0:                             uprv_strcpy(flagBuffer[idx], tmpFlagBuffer);
michael@0:                         } else {
michael@0:                             /* No match found.  Skip it. */
michael@0:                             continue;
michael@0:                         }
michael@0:                     } else {
michael@0:                         uprv_strcpy(flagBuffer[i++], tmpFlagBuffer);
michael@0:                     }
michael@0:                 }
michael@0:             }
michael@0:         }
michael@0:     } while (allocateMoreSpace && U_SUCCESS(*status));
michael@0: 
michael@0:     uprv_free(tmpFlagBuffer);
michael@0:     uprv_free(buffer);
michael@0: 
michael@0:     T_FileStream_close(f);
michael@0: 
michael@0:     if (U_SUCCESS(*status) && result == 0) {
michael@0:         currentBufferSize = DEFAULT_BUFFER_SIZE;
michael@0:     }
michael@0: 
michael@0:     return result;
michael@0: }
michael@0: 
michael@0: 
michael@0: /*
michael@0:  * Extract the setting after the '=' and store it in flag excluding the newline character.
michael@0:  */
michael@0: static int32_t extractFlag(char* buffer, int32_t bufferSize, char* flag, int32_t flagSize, const char **flagNames, int32_t numOfFlags, UErrorCode *status) {
michael@0:     int32_t i, idx = -1;
michael@0:     char *pBuffer;
michael@0:     int32_t offset=0;
michael@0:     UBool bufferWritten = FALSE;
michael@0: 
michael@0:     if (buffer[0] != 0) {
michael@0:         /* Get the offset (i.e. position after the '=') */
michael@0:         offset = getFlagOffset(buffer, bufferSize);
michael@0:         pBuffer = buffer+offset;
michael@0:         for(i = 0;;i++) {
michael@0:             if (i >= flagSize) {
michael@0:                 *status = U_BUFFER_OVERFLOW_ERROR;
michael@0:                 return -1;
michael@0:             }
michael@0:             if (pBuffer[i+1] == 0) {
michael@0:                 /* Indicates a new line character. End here. */
michael@0:                 flag[i] = 0;
michael@0:                 break;
michael@0:             }
michael@0: 
michael@0:             flag[i] = pBuffer[i];
michael@0:             if (i == 0) {
michael@0:                 bufferWritten = TRUE;
michael@0:             }
michael@0:         }
michael@0:     }
michael@0: 
michael@0:     if (!bufferWritten) {
michael@0:         flag[0] = 0;
michael@0:     }
michael@0: 
michael@0:     if (flagNames != NULL && offset>0) {
michael@0:         offset--;  /* Move offset back 1 because of '='*/
michael@0:         for (i = 0; i < numOfFlags; i++) {
michael@0:             if (uprv_strncmp(buffer, flagNames[i], offset) == 0) {
michael@0:                 idx = i;
michael@0:                 break;
michael@0:             }
michael@0:         }
michael@0:     }
michael@0: 
michael@0:     return idx;
michael@0: }
michael@0: 
michael@0: /*
michael@0:  * Get the position after the '=' character.
michael@0:  */
michael@0: static int32_t getFlagOffset(const char *buffer, int32_t bufferSize) {
michael@0:     int32_t offset = 0;
michael@0: 
michael@0:     for (offset = 0; offset < bufferSize;offset++) {
michael@0:         if (buffer[offset] == '=') {
michael@0:             offset++;
michael@0:             break;
michael@0:         }
michael@0:     }
michael@0: 
michael@0:     if (offset == bufferSize || (offset - 1) == bufferSize) {
michael@0:         offset = 0;
michael@0:     }
michael@0: 
michael@0:     return offset;
michael@0: }