glslang-zig/glslang/MachineIndependent/Scan.h
Andrew Woloszyn a132af5b78 Updated the includer interface to allow relative includes.
This plumbs both the current file path and the include depth
back up to the includer. This allows the includer to properly
support relative paths.

This also replaces the string copy that was done during include
with a zero-copy method of accomplishing the same thing. This
prevents extra copies of entire files.
2016-03-21 10:19:45 -04:00

250 lines
8.8 KiB
C++

//
//Copyright (C) 2002-2005 3Dlabs Inc. Ltd.
//Copyright (C) 2013 LunarG, Inc.
//
//All rights reserved.
//
//Redistribution and use in source and binary forms, with or without
//modification, are permitted provided that the following conditions
//are met:
//
// Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
//
// Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following
// disclaimer in the documentation and/or other materials provided
// with the distribution.
//
// Neither the name of 3Dlabs Inc. Ltd. nor the names of its
// contributors may be used to endorse or promote products derived
// from this software without specific prior written permission.
//
//THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
//"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
//LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
//FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
//COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
//INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
//BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
//LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
//CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
//LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
//ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
//POSSIBILITY OF SUCH DAMAGE.
//
#ifndef _GLSLANG_SCAN_INCLUDED_
#define _GLSLANG_SCAN_INCLUDED_
#include "Versions.h"
namespace glslang {
// Use a global end-of-input character, so no tranlation is needed across
// layers of encapsulation. Characters are all 8 bit, and positive, so there is
// no aliasing of character 255 onto -1, for example.
const int EndOfInput = -1;
//
// A character scanner that seamlessly, on read-only strings, reads across an
// array of strings without assuming null termination.
//
class TInputScanner {
public:
TInputScanner(int n, const char* const s[], size_t L[], const char* const* names = nullptr, int b = 0, int f = 0, bool single = false) :
numSources(n),
sources(reinterpret_cast<const unsigned char* const *>(s)), // up to this point, common usage is "char*", but now we need positive 8-bit characters
lengths(L), currentSource(0), currentChar(0), stringBias(b), finale(f), singleLogical(single)
{
loc = new TSourceLoc[numSources];
for (int i = 0; i < numSources; ++i) {
loc[i].init();
}
if (names != nullptr) {
for (int i = 0; i < numSources; ++i)
loc[i].name = names[i];
}
loc[currentSource].string = -stringBias;
loc[currentSource].line = 1;
loc[currentSource].column = 0;
logicalSourceLoc.string = 0;
logicalSourceLoc.line = 1;
logicalSourceLoc.column = 0;
logicalSourceLoc.name = loc[0].name;
}
virtual ~TInputScanner()
{
delete [] loc;
}
// retrieve the next character and advance one character
int get()
{
if (currentSource >= numSources)
return EndOfInput;
int ret = peek();
++loc[currentSource].column;
++logicalSourceLoc.column;
if (ret == '\n') {
++loc[currentSource].line;
++logicalSourceLoc.line;
logicalSourceLoc.column = 0;
loc[currentSource].column = 0;
}
advance();
return ret;
}
// retrieve the next character, no advance
int peek()
{
if (currentSource >= numSources)
return EndOfInput;
// Make sure we do not read off the end of a string.
// N.B. Sources can have a length of 0.
int sourceToRead = currentSource;
size_t charToRead = currentChar;
while(charToRead >= lengths[sourceToRead]) {
charToRead = 0;
sourceToRead += 1;
if (sourceToRead >= numSources) {
return EndOfInput;
}
}
// Here, we care about making negative valued characters positive
return sources[sourceToRead][charToRead];
}
// go back one character
void unget()
{
if (currentChar > 0) {
--currentChar;
--loc[currentSource].column;
--logicalSourceLoc.column;
if (loc[currentSource].column < 0) {
// We've moved back past a new line. Find the
// previous newline (or start of the file) to compute
// the column count on the now current line.
size_t chIndex = currentChar;
while (chIndex > 0) {
if (sources[currentSource][chIndex] == '\n') {
break;
}
--chIndex;
}
logicalSourceLoc.column = (int)(currentChar - chIndex);
loc[currentSource].column = (int)(currentChar - chIndex);
}
} else {
do {
--currentSource;
} while (currentSource > 0 && lengths[currentSource] == 0);
if (lengths[currentSource] == 0) {
// set to 0 if we've backed up to the start of an empty string
currentChar = 0;
} else
currentChar = lengths[currentSource] - 1;
}
if (peek() == '\n') {
--loc[currentSource].line;
--logicalSourceLoc.line;
}
}
// for #line override
void setLine(int newLine)
{
logicalSourceLoc.line = newLine;
loc[getLastValidSourceIndex()].line = newLine;
}
// for #line override in filename based parsing
void setFile(const char* filename)
{
logicalSourceLoc.name = filename;
loc[getLastValidSourceIndex()].name = filename;
}
void setString(int newString)
{
logicalSourceLoc.string = newString;
loc[getLastValidSourceIndex()].string = newString;
logicalSourceLoc.name = nullptr;
loc[getLastValidSourceIndex()].name = nullptr;
}
// for #include content indentation
void setColumn(int col)
{
logicalSourceLoc.column = col;
loc[getLastValidSourceIndex()].column = col;
}
const TSourceLoc& getSourceLoc() const
{
if (singleLogical) {
return logicalSourceLoc;
} else {
return loc[std::max(0, std::min(currentSource, numSources - finale - 1))];
}
}
// Returns the index (starting from 0) of the most recent valid source string we are reading from.
int getLastValidSourceIndex() const { return std::min(currentSource, numSources - 1); }
void consumeWhiteSpace(bool& foundNonSpaceTab);
bool consumeComment();
void consumeWhitespaceComment(bool& foundNonSpaceTab);
bool scanVersion(int& version, EProfile& profile, bool& notFirstToken);
protected:
// advance one character
void advance()
{
++currentChar;
if (currentChar >= lengths[currentSource]) {
++currentSource;
if (currentSource < numSources) {
loc[currentSource].string = loc[currentSource - 1].string + 1;
loc[currentSource].line = 1;
loc[currentSource].column = 0;
}
while (currentSource < numSources && lengths[currentSource] == 0) {
++currentSource;
if (currentSource < numSources) {
loc[currentSource].string = loc[currentSource - 1].string + 1;
loc[currentSource].line = 1;
loc[currentSource].column = 0;
}
}
currentChar = 0;
}
}
int numSources; // number of strings in source
const unsigned char* const *sources; // array of strings; must be converted to positive values on use, to avoid aliasing with -1 as EndOfInput
const size_t *lengths; // length of each string
int currentSource;
size_t currentChar;
// This is for reporting what string/line an error occurred on, and can be overridden by #line.
// It remembers the last state of each source string as it is left for the next one, so unget()
// can restore that state.
TSourceLoc* loc; // an array
int stringBias; // the first string that is the user's string number 0
int finale; // number of internal strings after user's last string
TSourceLoc logicalSourceLoc;
bool singleLogical; // treats the strings as a single logical string.
// locations will be reported from the first string.
};
} // end namespace glslang
#endif // _GLSLANG_SCAN_INCLUDED_