Quellcode-Bibliothek main.c Sprache: C

/****************************************************************************
**
**  This file is part of GAP, a system for computational discrete algebra.
**
**  Copyright of GAP belongs to its developers, whose names are too numerous
**  to list here. Please refer to the COPYRIGHT file for details.
**
**  SPDX-License-Identifier: GPL-2.0-or-later
*/

#include "common.h"
#include "sysfiles.h"
#include "sysroots.h"
#include "sysstr.h"
#include "system.h"

#ifdef HPCGAP
#include "hpc/thread.h"
#endif

#include "config.h"

#include <stdlib.h>     // for getenv, realpath, ...
#include <string.h>     // for snprintf
#include <unistd.h>     // for access, readlink, ...

#if defined(__APPLE__) && defined(__MACH__)
// Workaround: TRUE / FALSE are also defined by the macOS Mach-O headers
#define ENUM_DYLD_BOOL
#include <mach-o/dyld.h>
#endif

extern int realmain(int argc, const char * argv[]);

/****************************************************************************
**
*F * * * * * * * * * * finding location of executable * * * * * * * * * * * *
*/

#ifdef SYS_DEFAULT_PATHS

static void SetupInitialGapRoot(const char * argv0)
{
    gap_strlcpy(SyDefaultRootPath, SYS_DEFAULT_PATHS, sizeof(SyDefaultRootPath));
}

#else

/****************************************************************************
**
** The function 'find_yourself' is based on code (C) 2015 Mark Whitis, under
** the MIT License : https://stackoverflow.com/a/34271901/928031
*/
static void
find_yourself(const char * argv0, char * result, size_t resultsize)
{
    GAP_ASSERT(resultsize >= GAP_PATH_MAX);

    char tmpbuf[GAP_PATH_MAX];

    // absolute path, like '/usr/bin/gap'
    if (argv0[0] == '/') {
        if (realpath(argv0, result) && !access(result, F_OK)) {
            return;    // success
        }
    }
    // relative path, like 'bin/gap.sh'
    else if (strchr(argv0, '/')) {
        if (!getcwd(tmpbuf, sizeof(tmpbuf)))
            return;
        gap_strlcat(tmpbuf, "/", sizeof(tmpbuf));
        gap_strlcat(tmpbuf, argv0, sizeof(tmpbuf));
        if (realpath(tmpbuf, result) && !access(result, F_OK)) {
            return;    // success
        }
    }
    // executable name, like 'gap'
    else {
        char pathenv[GAP_PATH_MAX], *saveptr, *pathitem;
        gap_strlcpy(pathenv, getenv("PATH"), sizeof(pathenv));
        pathitem = strtok_r(pathenv, ":", &saveptr);
        for (; pathitem; pathitem = strtok_r(NULL, ":", &saveptr)) {
            gap_strlcpy(tmpbuf, pathitem, sizeof(tmpbuf));
            gap_strlcat(tmpbuf, "/", sizeof(tmpbuf));
            gap_strlcat(tmpbuf, argv0, sizeof(tmpbuf));
            if (realpath(tmpbuf, result) && !access(result, F_OK)) {
                return;    // success
            }
        }
    }

    *result = 0;    // reset buffer after error
}

static void SetupGAPLocation(const char * argv0, char * GAPExecLocation)
{
    // In the code below, we keep resetting locBuf, as some of the methods we
    // try do not promise to leave the buffer empty on a failed return.
    char locBuf[GAP_PATH_MAX] = "";
    Int4 length = 0;

#if defined(__APPLE__) && defined(__MACH__)
    uint32_t len = sizeof(locBuf);
    if (_NSGetExecutablePath(locBuf, &len) != 0) {
        *locBuf = 0;    // reset buffer after error
    }
#endif

    // try Linux procfs
    if (!*locBuf) {
        ssize_t ret = readlink("/proc/self/exe", locBuf, sizeof(locBuf));
        if (ret < 0)
            *locBuf = 0;    // reset buffer after error
    }

    // try FreeBSD / DragonFly BSD procfs
    if (!*locBuf) {
        ssize_t ret = readlink("/proc/curproc/file", locBuf, sizeof(locBuf));
        if (ret < 0)
            *locBuf = 0;    // reset buffer after error
    }

    // try NetBSD procfs
    if (!*locBuf) {
        ssize_t ret = readlink("/proc/curproc/exe", locBuf, sizeof(locBuf));
        if (ret < 0)
            *locBuf = 0;    // reset buffer after error
    }

    // if we are still failing, go and search the path
    if (!*locBuf) {
        find_yourself(argv0, locBuf, GAP_PATH_MAX);
    }

    // resolve symlinks (if present)
    if (!realpath(locBuf, GAPExecLocation))
        *GAPExecLocation = 0;    // reset buffer after error

    // now strip the executable name off
    length = strlen(GAPExecLocation);
    while (length > 0 && GAPExecLocation[length] != '/') {
        GAPExecLocation[length] = 0;
        length--;
    }
}

/****************************************************************************
**
*F  SySetInitialGapRootPaths( <string> )  . . . . .  set the root directories
**
**  Set up GAP's initial root paths, based on the location of the
**  GAP executable.
*/
static void SySetInitialGapRootPaths(const char * GAPExecLocation)
{
    if (GAPExecLocation[0] != 0) {
        // GAPExecLocation might be a subdirectory of GAP root,
        // so we will go and search for the true GAP root.
        // We try stepping back up to two levels.
        char pathbuf[GAP_PATH_MAX];
        char initgbuf[GAP_PATH_MAX];
        strxcpy(pathbuf, GAPExecLocation, sizeof(pathbuf));
        for (Int i = 0; i < 3; ++i) {
            strxcpy(initgbuf, pathbuf, sizeof(initgbuf));
            strxcat(initgbuf, "lib/init.g", sizeof(initgbuf));

            if (SyIsReadableFile(initgbuf) == 0) {
                gap_strlcpy(SyDefaultRootPath, pathbuf, sizeof(SyDefaultRootPath));
                // escape from loop
                return;
            }
            // try up a directory level
            strxcat(pathbuf, "../", sizeof(pathbuf));
        }
    }
}

static void SetupInitialGapRoot(const char * argv0)
{
    char GAPExecLocation[GAP_PATH_MAX] = "";
    SetupGAPLocation(argv0, GAPExecLocation);
    SySetInitialGapRootPaths(GAPExecLocation);
}
#endif

int main(int argc, const char * argv[])
{
    InstallBacktraceHandlers();
    SetupInitialGapRoot(argv[0]);

#ifdef HPCGAP
    RunThreadedMain(realmain, argc, argv);
    return 0;
#else
    return realmain(argc, argv);
#endif
}

quality94%

¤ Die Informationen auf dieser Webseite wurden nach bestem Wissen sorgfältig zusammengestellt. Es wird jedoch weder Vollständigkeit, noch Richtigkeit, noch Qualität der bereit gestellten Informationen zugesichert.0.1Bemerkung: (vorverarbeitet) ¤

Wurzel

Suchen

Beweissystem der NASA

Beweissystem Isabelle

NIST Cobol Testsuite

Cephes Mathematical Library

Wiener Entwicklungsmethode

Haftungshinweis

Die Informationen auf dieser Webseite wurden nach bestem Wissen sorgfältig zusammengestellt. Es wird jedoch weder Vollständigkeit, noch Richtigkeit, noch Qualität der bereit gestellten Informationen zugesichert.

Bemerkung:

Die farbliche Syntaxdarstellung ist noch experimentell.