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diff --git a/kfile-plugins/ps/gscreator.cpp b/kfile-plugins/ps/gscreator.cpp
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+/* This file is part of the KDE libraries
+ Copyright (C) 2001 Malte Starostik <[email protected]>
+
+ Handling of EPS previews Copyright (C) 2003 Philipp Hullmann <[email protected]>
+
+ This library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Library General Public
+ License as published by the Free Software Foundation; either
+ version 2 of the License, or (at your option) any later version.
+
+ This library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Library General Public License for more details.
+
+ You should have received a copy of the GNU Library General Public License
+ along with this library; see the file COPYING.LIB. If not, write to
+ the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+ Boston, MA 02110-1301, USA.
+*/
+
+/* This function gets a path of a DVI, EPS, PS or PDF file and
+ produces a PNG-Thumbnail which is stored as a QImage
+
+ The program works as follows
+
+ 1. Test if file is a DVI file
+
+ 2. Create a child process (1), in which the
+ file is to be changed into a PNG
+
+ 3. Child-process (1) :
+
+ 4. If file is DVI continue with 6
+
+ 5. If file is no DVI continue with 9
+
+ 6. Create another child process (2), in which the DVI is
+ turned into PS using dvips
+
+ 7. Parent process (2) :
+ Turn the recently created PS file into a PNG file using gs
+
+ 8. continue with 10
+
+ 9. Turn the PS,PDF or EPS file into a PNG file using gs
+
+ 10. Parent process (1)
+ store data in a QImage
+*/
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+
+#include <assert.h>
+#include <ctype.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <signal.h>
+#ifdef HAVE_SYS_SELECT_H
+#include <sys/select.h>
+#endif
+#include <sys/time.h>
+#include <sys/wait.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <kdemacros.h>
+
+#include <qcolor.h>
+#include <qfile.h>
+#include <qimage.h>
+#include <qregexp.h>
+
+
+#include "gscreator.h"
+#include "dscparse_adapter.h"
+#include "dscparse.h"
+
+extern "C"
+{
+ KDE_EXPORT ThumbCreator *new_creator()
+ {
+ return new GSCreator;
+ }
+}
+
+// This PS snippet will be prepended to the actual file so that only
+// the first page is output.
+static const char *psprolog =
+ "%!PS-Adobe-3.0\n"
+ "/.showpage.orig /showpage load def\n"
+ "/.showpage.firstonly {\n"
+ " .showpage.orig\n"
+ " quit\n"
+ "} def\n"
+ "/showpage { .showpage.firstonly } def\n";
+
+// This is the code recommended by Adobe tech note 5002 for including
+// EPS files.
+static const char *epsprolog =
+ "%!PS-Adobe-3.0\n"
+ "userdict begin /pagelevel save def /showpage { } def\n"
+ "0 setgray 0 setlinecap 1 setlinewidth 0 setlinejoin 10 setmiterlimit\n"
+ "[ ] 0 setdash newpath false setoverprint false setstrokeadjust\n";
+
+static const char * gsargs_ps[] = {
+ "gs",
+ "-sDEVICE=png16m",
+ "-sOutputFile=-",
+ "-dSAFER",
+ "-dPARANOIDSAFER",
+ "-dNOPAUSE",
+ "-dFirstPage=1",
+ "-dLastPage=1",
+ "-q",
+ "-",
+ 0, // file name
+ "-c",
+ "showpage",
+ "-c",
+ "quit",
+ 0
+};
+
+static const char * gsargs_eps[] = {
+ "gs",
+ "-sDEVICE=png16m",
+ "-sOutputFile=-",
+ "-dSAFER",
+ "-dPARANOIDSAFER",
+ "-dNOPAUSE",
+ 0, // page size
+ 0, // resolution
+ "-q",
+ "-",
+ 0, // file name
+ "-c",
+ "pagelevel",
+ "-c",
+ "restore",
+ "-c",
+ "end",
+ "-c",
+ "showpage",
+ "-c",
+ "quit",
+ 0
+};
+
+static const char *dvipsargs[] = {
+ "dvips",
+ "-n",
+ "1",
+ "-q",
+ "-o",
+ "-",
+ 0, // file name
+ 0
+};
+
+static bool correctDVI(const QString& filename);
+
+
+namespace {
+ bool got_sig_term = false;
+ void handle_sigterm( int ) {
+ got_sig_term = true;
+ }
+}
+
+
+bool GSCreator::create(const QString &path, int width, int height, QImage &img)
+{
+// The code in the loop (when testing whether got_sig_term got set)
+// should read some variation of:
+// parentJob()->wasKilled()
+//
+// Unfortunatelly, that's currently impossible without breaking BIC.
+// So we need to catch the signal ourselves.
+// Otherwise, on certain funny PS files (for example
+// http://www.tjhsst.edu/~Eedanaher/pslife/life.ps )
+// gs would run forever after we were dead.
+// #### Reconsider for KDE 4 ###
+// (24/12/03 - luis_pedro)
+//
+ typedef void ( *sighandler_t )( int );
+ // according to linux's "man signal" the above typedef is a gnu extension
+ sighandler_t oldhandler = signal( SIGTERM, handle_sigterm );
+
+ int input[2];
+ int output[2];
+ int dvipipe[2];
+
+ QByteArray data(1024);
+
+ bool ok = false;
+
+ // Test if file is DVI
+ bool no_dvi =!correctDVI(path);
+
+ if (pipe(input) == -1) {
+ return false;
+ }
+ if (pipe(output) == -1) {
+ close(input[0]);
+ close(input[1]);
+ return false;
+ }
+
+ KDSC dsc;
+ endComments = false;
+ dsc.setCommentHandler(this);
+
+ if (no_dvi)
+ {
+ FILE* fp = fopen(QFile::encodeName(path), "r");
+ if (fp == 0) return false;
+
+ char buf[4096];
+ int count;
+ while ((count = fread(buf, sizeof(char), 4096, fp)) != 0
+ && !endComments) {
+ dsc.scanData(buf, count);
+ }
+ fclose(fp);
+
+ if (dsc.pjl() || dsc.ctrld()) {
+ // this file is a mess.
+ return false;
+ }
+ }
+
+ const bool is_encapsulated = no_dvi &&
+ (path.find(QRegExp("\\.epsi?$", false, false)) > 0) &&
+ (dsc.bbox()->width() > 0) && (dsc.bbox()->height() > 0) &&
+ (dsc.page_count() <= 1);
+
+ char translation[64] = "";
+ char pagesize[32] = "";
+ char resopt[32] = "";
+ std::auto_ptr<KDSCBBOX> bbox = dsc.bbox();
+ if (is_encapsulated) {
+ // GhostScript's rendering at the extremely low resolutions
+ // required for thumbnails leaves something to be desired. To
+ // get nicer images, we render to four times the required
+ // resolution and let QImage scale the result.
+ const int hres = (width * 72) / bbox->width();
+ const int vres = (height * 72) / bbox->height();
+ const int resolution = (hres > vres ? vres : hres) * 4;
+ const int gswidth = ((bbox->urx() - bbox->llx()) * resolution) / 72;
+ const int gsheight = ((bbox->ury() - bbox->lly()) * resolution) / 72;
+
+ snprintf(pagesize, 31, "-g%ix%i", gswidth, gsheight);
+ snprintf(resopt, 31, "-r%i", resolution);
+ snprintf(translation, 63,
+ " 0 %i sub 0 %i sub translate\n", bbox->llx(),
+ bbox->lly());
+ }
+
+ const CDSC_PREVIEW_TYPE previewType =
+ static_cast<CDSC_PREVIEW_TYPE>(dsc.preview());
+
+ switch (previewType) {
+ case CDSC_TIFF:
+ case CDSC_WMF:
+ case CDSC_PICT:
+ // FIXME: these should take precedence, since they can hold
+ // color previews, which EPSI can't (or can it?).
+ break;
+ case CDSC_EPSI:
+ {
+ const int xscale = bbox->width() / width;
+ const int yscale = bbox->height() / height;
+ const int scale = xscale < yscale ? xscale : yscale;
+ if (getEPSIPreview(path,
+ dsc.beginpreview(),
+ dsc.endpreview(),
+ img,
+ bbox->width() / scale,
+ bbox->height() / scale))
+ return true;
+ // If the preview extraction routine fails, gs is used to
+ // create a thumbnail.
+ }
+ break;
+ case CDSC_NOPREVIEW:
+ default:
+ // need to run ghostscript in these cases
+ break;
+ }
+
+ pid_t pid = fork();
+ if (pid == 0) {
+ // Child process (1)
+
+ // close(STDERR_FILENO);
+
+ // find first zero entry in gsargs and put the filename
+ // or - (stdin) there, if DVI
+ const char **gsargs = gsargs_ps;
+ const char **arg = gsargs;
+
+ if (no_dvi && is_encapsulated) {
+ gsargs = gsargs_eps;
+ arg = gsargs;
+
+ // find first zero entry and put page size there
+ while (*arg) ++arg;
+ *arg = pagesize;
+
+ // find second zero entry and put resolution there
+ while (*arg) ++arg;
+ *arg = resopt;
+ }
+
+ // find next zero entry and put the filename there
+ QCString fname = QFile::encodeName( path );
+ while (*arg)
+ ++arg;
+ if( no_dvi )
+ *arg = fname.data();
+ else
+ *arg = "-";
+
+ // find first zero entry in dvipsargs and put the filename there
+ arg = dvipsargs;
+ while (*arg)
+ ++arg;
+ *arg = fname.data();
+
+ if( !no_dvi ){
+ pipe(dvipipe);
+ pid_t pid_two = fork();
+ if( pid_two == 0 ){
+ // Child process (2), reopen stdout on the pipe "dvipipe" and exec dvips
+
+ close(input[0]);
+ close(input[1]);
+ close(output[0]);
+ close(output[1]);
+ close(dvipipe[0]);
+
+ dup2( dvipipe[1], STDOUT_FILENO);
+
+ execvp(dvipsargs[0], const_cast<char *const *>(dvipsargs));
+ exit(1);
+ }
+ else if(pid_two != -1){
+ close(input[1]);
+ close(output[0]);
+ close(dvipipe[1]);
+
+ dup2( dvipipe[0], STDIN_FILENO);
+ dup2( output[1], STDOUT_FILENO);
+
+ execvp(gsargs[0], const_cast<char *const *>(gsargs));
+ exit(1);
+ }
+ else{
+ // fork() (2) failed, close these
+ close(dvipipe[0]);
+ close(dvipipe[1]);
+ }
+
+ }
+ else if( no_dvi ){
+ // Reopen stdin/stdout on the pipes and exec gs
+ close(input[1]);
+ close(output[0]);
+
+ dup2(input[0], STDIN_FILENO);
+ dup2(output[1], STDOUT_FILENO);
+
+ execvp(gsargs[0], const_cast<char *const *>(gsargs));
+ exit(1);
+ }
+ }
+ else if (pid != -1) {
+ // Parent process, write first-page-only-hack (the hack is not
+ // used if DVI) and read the png output
+ close(input[0]);
+ close(output[1]);
+ const char *prolog;
+ if (is_encapsulated)
+ prolog = epsprolog;
+ else
+ prolog = psprolog;
+ int count = write(input[1], prolog, strlen(prolog));
+ if (is_encapsulated)
+ write(input[1], translation, strlen(translation));
+
+ close(input[1]);
+ if (count == static_cast<int>(strlen(prolog))) {
+ int offset = 0;
+ while (!ok) {
+ fd_set fds;
+ FD_ZERO(&fds);
+ FD_SET(output[0], &fds);
+ struct timeval tv;
+ tv.tv_sec = 20;
+ tv.tv_usec = 0;
+
+ got_sig_term = false;
+ if (select(output[0] + 1, &fds, 0, 0, &tv) <= 0) {
+ if ( ( errno == EINTR || errno == EAGAIN ) && !got_sig_term ) continue;
+ break; // error, timeout or master wants us to quit (SIGTERM)
+ }
+ if (FD_ISSET(output[0], &fds)) {
+ count = read(output[0], data.data() + offset, 1024);
+ if (count == -1)
+ break;
+ else
+ if (count) // prepare for next block
+ {
+ offset += count;
+ data.resize(offset + 1024);
+ }
+ else // got all data
+ {
+ data.resize(offset);
+ ok = true;
+ }
+ }
+ }
+ }
+ if (!ok) // error or timeout, gs probably didn't exit yet
+ {
+ kill(pid, SIGTERM);
+ }
+
+ int status = 0;
+ if (waitpid(pid, &status, 0) != pid || (status != 0 && status != 256) )
+ ok = false;
+ }
+ else {
+ // fork() (1) failed, close these
+ close(input[0]);
+ close(input[1]);
+ close(output[1]);
+ }
+ close(output[0]);
+
+ int l = img.loadFromData( data );
+
+ if ( got_sig_term &&
+ oldhandler != SIG_ERR &&
+ oldhandler != SIG_DFL &&
+ oldhandler != SIG_IGN ) {
+ oldhandler( SIGTERM ); // propagate the signal. Other things might rely on it
+ }
+ if ( oldhandler != SIG_ERR ) signal( SIGTERM, oldhandler );
+
+ return ok && l;
+}
+
+ThumbCreator::Flags GSCreator::flags() const
+{
+ return static_cast<Flags>(DrawFrame);
+}
+
+void GSCreator::comment(Name name)
+{
+ switch (name) {
+ case EndPreview:
+ case BeginProlog:
+ case Page:
+ endComments = true;
+ break;
+
+ default:
+ break;
+ }
+}
+
+// Quick function to check if the filename corresponds to a valid DVI
+// file. Returns true if <filename> is a DVI file, false otherwise.
+
+static bool correctDVI(const QString& filename)
+{
+ QFile f(filename);
+ if (!f.open(IO_ReadOnly))
+ return FALSE;
+
+ unsigned char test[4];
+ if ( f.readBlock( (char *)test,2)<2 || test[0] != 247 || test[1] != 2 )
+ return FALSE;
+
+ int n = f.size();
+ if ( n < 134 ) // Too short for a dvi file
+ return FALSE;
+ f.at( n-4 );
+
+ unsigned char trailer[4] = { 0xdf,0xdf,0xdf,0xdf };
+
+ if ( f.readBlock( (char *)test, 4 )<4 || strncmp( (char *)test, (char*) trailer, 4 ) )
+ return FALSE;
+ // We suppose now that the dvi file is complete and OK
+ return TRUE;
+}
+
+bool GSCreator::getEPSIPreview(const QString &path, long start, long
+ end, QImage &outimg, int imgwidth, int imgheight)
+{
+ FILE *fp;
+ fp = fopen(QFile::encodeName(path), "r");
+ if (fp == 0) return false;
+
+ const long previewsize = end - start + 1;
+
+ char *buf = (char *) malloc(previewsize);
+ fseek(fp, start, SEEK_SET);
+ int count = fread(buf, sizeof(char), previewsize - 1, fp);
+ fclose(fp);
+ buf[previewsize - 1] = 0;
+ if (count != previewsize - 1)
+ {
+ free(buf);
+ return false;
+ }
+
+ QString previewstr = QString::fromLatin1(buf);
+ free(buf);
+
+ int offset = 0;
+ while ((offset < previewsize) && !(previewstr[offset].isDigit())) offset++;
+ int digits = 0;
+ while ((offset + digits < previewsize) && previewstr[offset + digits].isDigit()) digits++;
+ int width = previewstr.mid(offset, digits).toInt();
+ offset += digits + 1;
+ while ((offset < previewsize) && !(previewstr[offset].isDigit())) offset++;
+ digits = 0;
+ while ((offset + digits < previewsize) && previewstr[offset + digits].isDigit()) digits++;
+ int height = previewstr.mid(offset, digits).toInt();
+ offset += digits + 1;
+ while ((offset < previewsize) && !(previewstr[offset].isDigit())) offset++;
+ digits = 0;
+ while ((offset + digits < previewsize) && previewstr[offset + digits].isDigit()) digits++;
+ int depth = previewstr.mid(offset, digits).toInt();
+
+ // skip over the rest of the BeginPreview comment
+ while ((offset < previewsize) &&
+ previewstr[offset] != '\n' &&
+ previewstr[offset] != '\r') offset++;
+ while ((offset < previewsize) && previewstr[offset] != '%') offset++;
+
+ unsigned int imagedepth;
+ switch (depth) {
+ case 1:
+ case 2:
+ case 4:
+ case 8:
+ imagedepth = 8;
+ break;
+ case 12: // valid, but not (yet) supported
+ default: // illegal value
+ return false;
+ }
+
+ unsigned int colors = (1U << depth);
+ QImage img(width, height, imagedepth, colors);
+ img.setAlphaBuffer(false);
+
+ if (imagedepth <= 8) {
+ for (unsigned int gray = 0; gray < colors; gray++) {
+ unsigned int grayvalue = (255U * (colors - 1 - gray)) /
+ (colors - 1);
+ img.setColor(gray, qRgb(grayvalue, grayvalue, grayvalue));
+ }
+ }
+
+ const unsigned int bits_per_scan_line = width * depth;
+ unsigned int bytes_per_scan_line = bits_per_scan_line / 8;
+ if (bits_per_scan_line % 8) bytes_per_scan_line++;
+ const unsigned int bindatabytes = height * bytes_per_scan_line;
+ QMemArray<unsigned char> bindata(bindatabytes);
+
+ for (unsigned int i = 0; i < bindatabytes; i++) {
+ if (offset >= previewsize)
+ return false;
+
+ while (!isxdigit(previewstr[offset].latin1()) &&
+ offset < previewsize)
+ offset++;
+
+ bool ok = false;
+ bindata[i] = static_cast<unsigned char>(previewstr.mid(offset, 2).toUInt(&ok, 16));
+ if (!ok)
+ return false;
+
+ offset += 2;
+ }
+
+ for (int scanline = 0; scanline < height; scanline++) {
+ unsigned char *scanlineptr = img.scanLine(scanline);
+
+ for (int pixelindex = 0; pixelindex < width; pixelindex++) {
+ unsigned char pixelvalue = 0;
+ const unsigned int bitoffset =
+ scanline * bytes_per_scan_line * 8U + pixelindex * depth;
+ for (int depthindex = 0; depthindex < depth;
+ depthindex++) {
+ const unsigned int byteindex = (bitoffset + depthindex) / 8U;
+ const unsigned int bitindex =
+ 7 - ((bitoffset + depthindex) % 8U);
+ const unsigned char bitvalue =
+ (bindata[byteindex] & static_cast<unsigned char>(1U << bitindex)) >> bitindex;
+ pixelvalue |= (bitvalue << depthindex);
+ }
+ scanlineptr[pixelindex] = pixelvalue;
+ }
+ }
+
+ outimg = img.convertDepth(32).smoothScale(imgwidth, imgheight);
+
+ return true;
+}
generated by cgit v1.2.1 (git 2.18.0) at 2024-12-25 05:34:29 +0000