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/*************************************************************************
*
* © 2016 and later: Unicode, Inc. and others.
* License & terms of use: http://www.unicode.org/copyright.html
*
**************************************************************************
**************************************************************************
*
* Copyright (C) 2002-2010, International Business Machines
* Corporation and others. All Rights Reserved.
*
***************************************************************************
*/
//
// ugrep - an ICU sample program illustrating the use of ICU Regular Expressions.
//
// The use of the ICU Regex API all occurs within the main()
// function. The rest of the code deals with opening files,
// encoding conversions, printing results, etc.
//
// This is not a full-featured grep program. The command line options
// have been kept to a minimum to avoid complicating the sample code.
//
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "unicode/utypes.h"
#include "unicode/ustring.h"
#include "unicode/regex.h"
#include "unicode/ucnv.h"
#include "unicode/uclean.h"
using namespace icu;
//
// The following variables contain parameters that may be set from the command line.
//
const char *pattern = nullptr; // The regular expression
int firstFileNum; // argv index of the first file name
UBool displayFileName = false;
UBool displayLineNum = false;
//
// Info regarding the file currently being processed
//
const char *fileName;
int fileLen; // Length, in UTF-16 Code Units.
char16_t *ucharBuf = nullptr; // Buffer, holds converted file. (Simple minded program, always reads
// the whole file at once.
char *charBuf = nullptr; // Buffer, for original, unconverted file data.
//
// Info regarding the line currently being processed
//
int lineStart; // Index of first char of the current line in the file buffer
int lineEnd; // Index of char following the new line sequence for the current line
int lineNum;
//
// Converter, used on output to convert Unicode data back to char *
// so that it will display in non-Unicode terminal windows.
//
UConverter *outConverter = nullptr;
//
// Function forward declarations
//
void processOptions(int argc, const char **argv);
void nextLine(int start);
void printMatch();
void printUsage();
void readFile(const char *name);
//------------------------------------------------------------------------------------------
//
// main for ugrep
//
// Structurally, all use of the ICU Regular Expression API is in main(),
// and all of the supporting stuff necessary to make a running program, but
// not directly related to regular expressions, is factored out into these other
// functions.
//
//------------------------------------------------------------------------------------------
int main(int argc, const char** argv) {
UBool matchFound = false;
//
// Process the command line options.
//
processOptions(argc, argv);
//
// Create a RegexPattern object from the user supplied pattern string.
//
UErrorCode status = U_ZERO_ERROR; // All ICU operations report success or failure
// in a status variable.
UParseError parseErr; // In the event of a syntax error in the regex pattern,
// this struct will contain the position of the
// error.
RegexPattern *rePat = RegexPattern::compile(pattern, parseErr, status);
// Note that C++ is doing an automatic conversion
// of the (char *) pattern to a temporary
// UnicodeString object.
if (U_FAILURE(status)) {
fprintf(stderr, "ugrep: error in pattern: \"%s\" at position %d\n",
u_errorName(status), parseErr.offset);
exit(-1);
}
//
// Create a RegexMatcher from the newly created pattern.
//
UnicodeString empty;
RegexMatcher *matcher = rePat->matcher(empty, status);
if (U_FAILURE(status)) {
fprintf(stderr, "ugrep: error in creating RegexMatcher: \"%s\"\n",
u_errorName(status));
exit(-1);
}
//
// Loop, processing each of the input files.
//
for (int fileNum=firstFileNum; fileNum < argc; fileNum++) {
readFile(argv[fileNum]);
//
// Loop through the lines of a file, trying to match the regex pattern on each.
//
for (nextLine(0); lineStart<fileLen; nextLine(lineEnd)) {
UnicodeString s(false, ucharBuf+lineStart, lineEnd-lineStart);
matcher->reset(s);
if (matcher->find()) {
matchFound = true;
printMatch();
}
}
}
//
// Clean up
//
delete matcher;
delete rePat;
free(ucharBuf);
free(charBuf);
ucnv_close(outConverter);
u_cleanup(); // shut down ICU, release any cached data it owns.
return matchFound? 0: 1;
}
//------------------------------------------------------------------------------------------
//
// doOptions Run through the command line options, and set
// the global variables accordingly.
//
// exit without returning if an error occurred and
// ugrep should not proceed further.
//
//------------------------------------------------------------------------------------------
void processOptions(int argc, const char **argv) {
int optInd;
UBool doUsage = false;
UBool doVersion = false;
const char *arg;
for(optInd = 1; optInd < argc; ++optInd) {
arg = argv[optInd];
/* version info */
if(strcmp(arg, "-V") == 0 || strcmp(arg, "--version") == 0) {
doVersion = true;
}
/* usage info */
else if(strcmp(arg, "--help") == 0) {
doUsage = true;
}
else if(strcmp(arg, "-n") == 0 || strcmp(arg, "--line-number") == 0) {
displayLineNum = true;
}
/* POSIX.1 says all arguments after -- are not options */
else if(strcmp(arg, "--") == 0) {
/* skip the -- */
++optInd;
break;
}
/* unrecognized option */
else if(strncmp(arg, "-", strlen("-")) == 0) {
printf("ugrep: invalid option -- %s\n", arg+1);
doUsage = true;
}
/* done with options */
else {
break;
}
}
if (doUsage) {
printUsage();
exit(0);
}
if (doVersion) {
printf("ugrep version 0.01\n");
if (optInd == argc) {
exit(0);
}
}
int remainingArgs = argc-optInd; // pattern file ...
if (remainingArgs < 2) {
fprintf(stderr, "ugrep: files or pattern are missing.\n");
printUsage();
exit(1);
}
if (remainingArgs > 2) {
// More than one file to be processed. Display file names with match output.
displayFileName = true;
}
pattern = argv[optInd];
firstFileNum = optInd+1;
}
//------------------------------------------------------------------------------------------
//
// printUsage
//
//------------------------------------------------------------------------------------------
void printUsage() {
printf("ugrep [options] pattern file...\n"
" -V or --version display version information\n"
" --help display this help and exit\n"
" -- stop further option processing\n"
"-n, --line-number Prefix each line of output with the line number within its input file.\n"
);
exit(0);
}
//------------------------------------------------------------------------------------------
//
// readFile Read a file into memory, and convert it to Unicode.
//
// Since this is just a demo program, take the simple minded approach
// of always reading the whole file at once. No intelligent buffering
// is done.
//
//------------------------------------------------------------------------------------------
void readFile(const char *name) {
//
// Initialize global file variables
//
fileName = name;
fileLen = 0; // zero length prevents processing in case of errors.
//
// Open the file and determine its size.
//
FILE *file = fopen(name, "rb");
if (file == nullptr) {
fprintf(stderr, "ugrep: Could not open file \"%s\"\n", fileName);
return;
}
fseek(file, 0, SEEK_END);
int rawFileLen = ftell(file);
fseek(file, 0, SEEK_SET);
//
// Read in the file
//
charBuf = static_cast<char*>(realloc(charBuf, rawFileLen + 1)); // Need error checking...
int t = static_cast<int>(fread(charBuf, 1, rawFileLen, file));
if (t != rawFileLen) {
fprintf(stderr, "Error reading file \"%s\"\n", fileName);
fclose(file);
return;
}
charBuf[rawFileLen]=0;
fclose(file);
//
// Look for a Unicode Signature (BOM) in the data
//
int32_t signatureLength;
const char * charDataStart = charBuf;
UErrorCode status = U_ZERO_ERROR;
const char* encoding = ucnv_detectUnicodeSignature(
charDataStart, rawFileLen, &signatureLength, &status);
if (U_FAILURE(status)) {
fprintf(stderr, "ugrep: ICU Error \"%s\" from ucnv_detectUnicodeSignature()\n",
u_errorName(status));
return;
}
if(encoding!=nullptr ){
charDataStart += signatureLength;
rawFileLen -= signatureLength;
}
//
// Open a converter to take the file to UTF-16
//
UConverter* conv;
conv = ucnv_open(encoding, &status);
if (U_FAILURE(status)) {
fprintf(stderr, "ugrep: ICU Error \"%s\" from ucnv_open()\n", u_errorName(status));
return;
}
//
// Convert the file data to char16_t.
// Preflight first to determine required buffer size.
//
uint32_t destCap = ucnv_toUChars(conv,
nullptr, // dest,
0, // destCapacity,
charDataStart,
rawFileLen,
&status);
if (status != U_BUFFER_OVERFLOW_ERROR) {
fprintf(stderr, "ugrep: ucnv_toUChars: ICU Error \"%s\"\n", u_errorName(status));
return;
};
status = U_ZERO_ERROR;
ucharBuf = static_cast<char16_t*>(realloc(ucharBuf, (destCap + 1) * sizeof(char16_t)));
ucnv_toUChars(conv,
ucharBuf, // dest,
destCap+1,
charDataStart,
rawFileLen,
&status);
if (U_FAILURE(status)) {
fprintf(stderr, "ugrep: ucnv_toUChars: ICU Error \"%s\"\n", u_errorName(status));
return;
};
ucnv_close(conv);
//
// Successful conversion. Set the global size variables so that
// the rest of the processing will proceed for this file.
//
fileLen = destCap;
}
//------------------------------------------------------------------------------------------
//
// nextLine Advance the line index variables, starting at the
// specified position in the input file buffer, by
// scanning forward until the next end-of-line.
//
// Need to take into account all of the possible Unicode
// line ending sequences.
//
//------------------------------------------------------------------------------------------
void nextLine(int startPos) {
if (startPos == 0) {
lineNum = 0;
} else {
lineNum++;
}
lineStart = lineEnd = startPos;
for (;;) {
if (lineEnd >= fileLen) {
return;
}
char16_t c = ucharBuf[lineEnd];
lineEnd++;
if (c == 0x0a || // Line Feed
c == 0x0c || // Form Feed
c == 0x0d || // Carriage Return
c == 0x85 || // Next Line
c == 0x2028 || // Line Separator
c == 0x2029) // Paragraph separator
{
break;
}
}
// Check for CR/LF sequence, and advance over the LF if we're in the middle of one.
if (lineEnd < fileLen &&
ucharBuf[lineEnd-1] == 0x0d &&
ucharBuf[lineEnd] == 0x0a)
{
lineEnd++;
}
}
//------------------------------------------------------------------------------------------
//
// printMatch Called when a matching line has been located.
// Print out the line from the file with the match, after
// converting it back to the default code page.
//
//------------------------------------------------------------------------------------------
void printMatch() {
char buf[2000];
UErrorCode status = U_ZERO_ERROR;
// If we haven't already created a converter for output, do it now.
if (outConverter == nullptr) {
outConverter = ucnv_open(nullptr, &status);
if (U_FAILURE(status)) {
fprintf(stderr, "ugrep: Error opening default converter: \"%s\"\n",
u_errorName(status));
exit(-1);
}
};
// Convert the line to be printed back to the default 8 bit code page.
// If the line is too long for our buffer, just truncate it.
ucnv_fromUChars(outConverter,
buf, // destination buffer for conversion
sizeof(buf), // capacity of destination buffer
&ucharBuf[lineStart], // Input to conversion
lineEnd-lineStart, // number of UChars to convert
&status);
buf[sizeof(buf)-1] = 0; // Add null for use in case of too long lines.
// The converter null-terminates its output unless
// the buffer completely fills.
if (displayFileName) {
printf("%s:", fileName);
}
if (displayLineNum) {
printf("%d:", lineNum);
}
printf("%s", buf);
}
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