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author | Jörg Frings-Fürst <debian@jff-webhosting.net> | 2017-04-29 12:11:08 +0200 |
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committer | Jörg Frings-Fürst <debian@jff-webhosting.net> | 2017-04-29 12:11:08 +0200 |
commit | 16e9630b79f0a7a90c6cedb6781175bb8b337dc1 (patch) | |
tree | e1b09d277dec2057e6b995ec099dd2b1f2129b35 /app/wlib/gtklib/osxhelp.c | |
parent | 09795a01ef859f072920de9df974d1b03b9ab9a4 (diff) |
New upstream version 4.3.0upstream/4.3.0
Diffstat (limited to 'app/wlib/gtklib/osxhelp.c')
-rw-r--r-- | app/wlib/gtklib/osxhelp.c | 133 |
1 files changed, 133 insertions, 0 deletions
diff --git a/app/wlib/gtklib/osxhelp.c b/app/wlib/gtklib/osxhelp.c new file mode 100644 index 0000000..829ec94 --- /dev/null +++ b/app/wlib/gtklib/osxhelp.c @@ -0,0 +1,133 @@ +/** \file osxhelp.c + * use OSX Help system + */ + +/* XTrkCad - Model Railroad CAD + * Copyright (C) 2015 Martin Fischer + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program 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 General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. + */ + +#include <stdio.h> +#include <stdlib.h> +#include <sys/stat.h> +#include <sys/wait.h> +#include <string.h> +#include <errno.h> +#include <fcntl.h> + +#include "gtkint.h" +#include "i18n.h" + +#define HELPCOMMANDPIPE "/tmp/helppipe" +#define EXITCOMMAND "##exit##" +#define HELPERPROGRAM "helphelper" + +static pid_t pidOfChild; +static int handleOfPipe; +extern char *wExecutableName; + +/** + * Create the fully qualified filename for the help helper + * + * \param parent IN path and filename of parent process + * \return filename for the child process + */ + +static +char *ChildProgramFile(char *parentProgram) +{ + char *startOfFilename; + char *childProgram; + + childProgram = malloc(strlen(parentProgram)+ sizeof(HELPERPROGRAM) + 1); + strcpy(childProgram, parentProgram); + startOfFilename = strrchr(childProgram, '/'); + strcpy(startOfFilename + 1, HELPERPROGRAM); + + return (childProgram); +} + + +/** + * Invoke the help system to display help for <topic>. + * + * \param topic IN topic string + */ + +void wHelp(const char * topic) +{ + pid_t newPid; + int len; + int status; + const char html[] = ".html"; + char *page; + + // check whether child already exists + if (pidOfChild != 0) { + if (waitpid(pidOfChild, &status, WNOHANG) > 0) { + // child exited -> clean up + close(handleOfPipe); + unlink(HELPCOMMANDPIPE); + handleOfPipe = 0; + pidOfChild = 0; // child exited + } + } + + // (re)start child + if (pidOfChild == 0) { + mkfifo(HELPCOMMANDPIPE, 0666); + newPid = fork(); /* New process starts here */ + + if (newPid > 0) { + pidOfChild = newPid; + } else if (newPid == 0) { + char *child = ChildProgramFile(wExecutableName); + + if (execlp(child, child, NULL) < 0) { /* never normally returns */ + exit(8); + } + + free(child); + } else { /* -1 signifies fork failure */ + pidOfChild = 0; + return; + } + } + + if (!handleOfPipe) { + handleOfPipe = open(HELPCOMMANDPIPE, O_WRONLY); + + if (handleOfPipe < 0) { + kill(pidOfChild, SIGKILL); /* tidy up on next call */ + } + + } + + page = malloc(strlen(topic) + strlen(html) + 1); + + if (!page) { + return; + } + + strcpy(page, topic); + strcat(page, html); + len = strlen(page); + + write(handleOfPipe, &len, sizeof(int)); + write(handleOfPipe, page, strlen(page)+1); + + free(page); +} |