/*      $NetBSD: compat.c,v 1.268 2025/07/06 07:11:31 rillig Exp $      */

/*
 * Copyright (c) 1988, 1989, 1990 The Regents of the University of California.
 * All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Adam de Boor.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. 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.
 * 3. Neither the name of the University 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 REGENTS 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 REGENTS 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.
 */

/*
 * Copyright (c) 1988, 1989 by Adam de Boor
 * Copyright (c) 1989 by Berkeley Softworks
 * All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Adam de Boor.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. 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.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *      This product includes software developed by the University of
 *      California, Berkeley and its contributors.
 * 4. Neither the name of the University 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 REGENTS 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 REGENTS 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.
 */

/*
 * This file implements the full-compatibility mode of make, which makes the
 * targets without parallelism and without a custom shell.
 *
 * Interface:
 *      Compat_MakeAll  Initialize this module and make the given targets.
 */

#include <sys/types.h>
#include <sys/stat.h>
#include <sys/wait.h>

#include <errno.h>
#include <signal.h>

#include "make.h"
#include "dir.h"
#include "job.h"
#ifdef USE_META
# include "meta.h"
#endif
#include "metachar.h"
#include "pathnames.h"

/*      "@(#)compat.c   8.2 (Berkeley) 3/19/94" */
MAKE_RCSID("$NetBSD: compat.c,v 1.268 2025/07/06 07:11:31 rillig Exp $");

static GNode *curTarg;
static pid_t compatChild;
static int compatSigno;

/*
 * Delete the file of a failed, interrupted, or otherwise duffed target,
 * unless inhibited by .PRECIOUS.
 */
static void
CompatDeleteTarget(GNode *gn)
{
        if (!GNode_IsPrecious(gn) &&
            (gn->type & OP_PHONY) == 0) {
                const char *file = GNode_VarTarget(gn);
                if (!opts.noExecute && unlink_file(file) == 0)
                        Error("*** %s removed", file);
        }
}

/*
 * Interrupt the creation of the current target and remove it if it ain't
 * precious. Then exit.
 *
 * If .INTERRUPT exists, its commands are run first WITH INTERRUPTS IGNORED.
 *
 * XXX: is .PRECIOUS supposed to inhibit .INTERRUPT? I doubt it, but I've
 * left the logic alone for now. - dholland 20160826
 */
static void
CompatInterrupt(int signo)
{
        if (curTarg != NULL) {
                CompatDeleteTarget(curTarg);
                if (signo == SIGINT && !GNode_IsPrecious(curTarg)) {
                        GNode *gn = Targ_FindNode(".INTERRUPT");
                        if (gn != NULL)
                                Compat_Make(gn, gn);
                }
        }

        if (signo == SIGQUIT)
                _exit(signo);

        /*
         * If there is a child running, pass the signal on.
         * We will exist after it has exited.
         */
        compatSigno = signo;
        if (compatChild > 0) {
                KILLPG(compatChild, signo);
        } else {
                bmake_signal(signo, SIG_DFL);
                kill(myPid, signo);
        }
}

static void
DebugFailedTarget(const char *cmd, const GNode *gn)
{
        const char *p = cmd;
        debug_printf("\n*** Failed target:  %s\n*** Failed command: ",
            gn->name);

        /*
         * Replace runs of whitespace with a single space, to reduce the
         * amount of whitespace for multi-line command lines.
         */
        while (*p != '\0') {
                if (ch_isspace(*p)) {
                        debug_printf(" ");
                        cpp_skip_whitespace(&p);
                } else {
                        debug_printf("%c", *p);
                        p++;
                }
        }
        debug_printf("\n");
}

static bool
UseShell(const char *cmd MAKE_ATTR_UNUSED)
{
#if !defined(MAKE_NATIVE)
        /*
         * In a non-native build, the host environment might be weird enough
         * that it's necessary to go through a shell to get the correct
         * behaviour.  Or perhaps the shell has been replaced with something
         * that does extra logging, and that should not be bypassed.
         */
        return true;
#else
        /*
         * Search for meta characters in the command. If there are no meta
         * characters, there's no need to execute a shell to execute the
         * command.
         *
         * Additionally variable assignments and empty commands
         * go to the shell. Therefore treat '=' and ':' like shell
         * meta characters as documented in make(1).
         */

        return needshell(cmd);
#endif
}

static int
Compat_Spawn(const char **av)
{
        int pid = FORK_FUNCTION();
        if (pid < 0)
                Fatal("Could not fork");

        if (pid == 0) {
#ifdef USE_META
                if (useMeta)
                        meta_compat_child();
#endif
                (void)execvp(av[0], (char *const *)UNCONST(av));
                execDie("exec", av[0]);
        }
        return pid;
}

/*
 * Execute the next command for a target. If the command returns an error,
 * the node's made field is set to ERROR and creation stops.
 *
 * Input:
 *      cmdp            Command to execute
 *      gn              Node from which the command came
 *      ln              List node that contains the command
 *
 * Results:
 *      true if the command succeeded.
 */
bool
Compat_RunCommand(const char *cmdp, GNode *gn, StringListNode *ln)
{
        char *cmdStart;         /* Start of expanded command */
        char *volatile bp;
        bool silent;            /* Don't print command */
        bool doIt;              /* Execute even if -n */
        volatile bool errCheck; /* Check errors */
        int reason;             /* Reason for child's death */
        int status;             /* Description of child's death */
        pid_t retstat;          /* Result of wait */
        const char **av;        /* Arguments for the child process */
        char **volatile mav;    /* Copy of the argument vector for freeing */
        bool useShell;          /* True if command should be executed using a
                                 * shell */
        const char *cmd = cmdp;
        char cmd_file[MAXPATHLEN];
        size_t cmd_len;
        int parseErrorsBefore;

        silent = (gn->type & OP_SILENT) != OP_NONE;
        errCheck = !(gn->type & OP_IGNORE);
        doIt = false;

        parseErrorsBefore = parseErrors;
        cmdStart = Var_SubstInTarget(cmd, gn);
        if (parseErrors != parseErrorsBefore) {
                free(cmdStart);
                return false;
        }

        if (cmdStart[0] == '\0') {
                free(cmdStart);
                return true;
        }
        cmd = cmdStart;
        LstNode_Set(ln, cmdStart);

        if (gn->type & OP_SAVE_CMDS) {
                GNode *endNode = Targ_GetEndNode();
                if (gn != endNode) {
                        /*
                         * Append the expanded command, to prevent the
                         * local variables from being interpreted in the
                         * scope of the .END node.
                         *
                         * A probably unintended side effect of this is that
                         * the expanded command will be expanded again in the
                         * .END node.  Therefore, a literal '$' in these
                         * commands must be written as '$$$$' instead of the
                         * usual '$$'.
                         */
                        Lst_Append(&endNode->commands, cmdStart);
                        goto register_command;
                }
        }
        if (strcmp(cmdStart, "...") == 0) {
                gn->type |= OP_SAVE_CMDS;
        register_command:
                Parse_RegisterCommand(cmdStart);
                return true;
        }

        for (;;) {
                if (*cmd == '@')
                        silent = !DEBUG(LOUD);
                else if (*cmd == '-')
                        errCheck = false;
                else if (*cmd == '+')
                        doIt = true;
                else if (!ch_isspace(*cmd))
                        /* Ignore whitespace for compatibility with gnu make */
                        break;
                cmd++;
        }

        if (cmd[0] == '\0')
                goto register_command;

        useShell = UseShell(cmd);

        if (!silent || !GNode_ShouldExecute(gn)) {
                printf("%s\n", cmd);
                fflush(stdout);
        }

        if (!doIt && !GNode_ShouldExecute(gn))
                goto register_command;

        DEBUG1(JOB, "Execute: '%s'\n", cmd);

        cmd_len = strlen(cmd);
        if (cmd_len > MAKE_CMDLEN_LIMIT)
                useShell = true;
        else
                cmd_file[0] = '\0';

        if (useShell) {
                static const char *shargv[5];

                Cmd_Argv(cmd, cmd_len, shargv, cmd_file, sizeof(cmd_file),
                    errCheck && shellErrFlag != NULL, DEBUG(SHELL));
                av = shargv;
                bp = NULL;
                mav = NULL;
        } else {
                Words words = Str_Words(cmd, false);
                mav = words.words;
                bp = words.freeIt;
                av = (void *)mav;
        }

#ifdef USE_META
        if (useMeta)
                meta_compat_start();
#endif

        Var_ReexportVars(gn);
        Var_ExportStackTrace(gn->name, cmd);

        compatChild = Compat_Spawn(av);
        free(mav);
        free(bp);

        /* XXX: Memory management looks suspicious here. */
        /* XXX: Setting a list item to NULL is unexpected. */
        LstNode_SetNull(ln);

#ifdef USE_META
        if (useMeta)
                meta_compat_parent(compatChild);
#endif

        /* The child is off and running. Now all we can do is wait... */
        while ((retstat = wait(&reason)) != compatChild) {
                if (retstat > 0)
                        JobReapChild(retstat, reason, false); /* not ours? */
                if (retstat == -1 && errno != EINTR)
                        break;
        }

        if (retstat < 0)
                Fatal("error in wait: %d: %s", retstat, strerror(errno));

        if (WIFSTOPPED(reason)) {
                status = WSTOPSIG(reason);
        } else if (WIFEXITED(reason)) {
                status = WEXITSTATUS(reason);
#if defined(USE_META) && defined(USE_FILEMON_ONCE)
                if (useMeta)
                        meta_cmd_finish(NULL);
#endif
                if (status != 0) {
                        if (DEBUG(ERROR))
                                DebugFailedTarget(cmd, gn);
                        printf("*** Error code %d", status);
                }
        } else {
                status = WTERMSIG(reason);
                printf("*** Signal %d", status);
        }


        if (!WIFEXITED(reason) || status != 0) {
                if (errCheck) {
#ifdef USE_META
                        if (useMeta)
                                meta_job_error(NULL, gn, false, status);
#endif
                        gn->made = ERROR;
                        if (WIFEXITED(reason))
                                gn->exit_status = status;
                        if (opts.keepgoing) {
                                /*
                                 * Abort the current target,
                                 * but let others continue.
                                 */
                                printf(" (continuing)\n");
                        } else {
                                printf("\n");
                        }
                        if (deleteOnError)
                                CompatDeleteTarget(gn);
                } else {
                        /*
                         * Continue executing commands for this target.
                         * If we return 0, this will happen...
                         */
                        printf(" (ignored)\n");
                        status = 0;
                }
                fflush(stdout);
        }

        free(cmdStart);
        if (cmd_file[0] != '\0')
                unlink(cmd_file);
        compatChild = 0;
        if (compatSigno != 0) {
                bmake_signal(compatSigno, SIG_DFL);
                kill(myPid, compatSigno);
        }

        return status == 0;
}

static void
RunCommands(GNode *gn)
{
        StringListNode *ln;

        for (ln = gn->commands.first; ln != NULL; ln = ln->next) {
                const char *cmd = ln->datum;
                if (!Compat_RunCommand(cmd, gn, ln))
                        break;
        }
}

static void
MakeInRandomOrder(GNode **gnodes, GNode **end, GNode *pgn)
{
        GNode **it;
        size_t r;

        for (r = (size_t)(end - gnodes); r >= 2; r--) {
                /* Biased, but irrelevant in practice. */
                size_t i = (size_t)random() % r;
                GNode *t = gnodes[r - 1];
                gnodes[r - 1] = gnodes[i];
                gnodes[i] = t;
        }

        for (it = gnodes; it != end; it++)
                Compat_Make(*it, pgn);
}

static void
MakeWaitGroupsInRandomOrder(GNodeList *gnodes, GNode *pgn)
{
        Vector vec;
        GNodeListNode *ln;
        GNode **nodes;
        size_t i, n, start;

        Vector_Init(&vec, sizeof(GNode *));
        for (ln = gnodes->first; ln != NULL; ln = ln->next)
                *(GNode **)Vector_Push(&vec) = ln->datum;
        nodes = vec.items;
        n = vec.len;

        start = 0;
        for (i = 0; i < n; i++) {
                if (nodes[i]->type & OP_WAIT) {
                        MakeInRandomOrder(nodes + start, nodes + i, pgn);
                        Compat_Make(nodes[i], pgn);
                        start = i + 1;
                }
        }
        MakeInRandomOrder(nodes + start, nodes + i, pgn);

        Vector_Done(&vec);
}

static void
MakeNodes(GNodeList *gnodes, GNode *pgn)
{
        GNodeListNode *ln;

        if (Lst_IsEmpty(gnodes))
                return;
        if (opts.randomizeTargets) {
                MakeWaitGroupsInRandomOrder(gnodes, pgn);
                return;
        }

        for (ln = gnodes->first; ln != NULL; ln = ln->next) {
                GNode *cgn = ln->datum;
                Compat_Make(cgn, pgn);
        }
}

static bool
MakeUnmade(GNode *gn, GNode *pgn)
{

        assert(gn->made == UNMADE);

        /*
         * First mark ourselves to be made, then apply whatever transformations
         * the suffix module thinks are necessary. Once that's done, we can
         * descend and make all our children. If any of them has an error
         * but the -k flag was given, our 'make' field will be set to false
         * again. This is our signal to not attempt to do anything but abort
         * our parent as well.
         */
        gn->flags.remake = true;
        gn->made = BEINGMADE;

        if (!(gn->type & OP_MADE))
                Suff_FindDeps(gn);

        MakeNodes(&gn->children, gn);

        if (!gn->flags.remake) {
                gn->made = ABORTED;
                pgn->flags.remake = false;
                return false;
        }

        if (Lst_FindDatum(&gn->implicitParents, pgn) != NULL)
                Var_Set(pgn, IMPSRC, GNode_VarTarget(gn));

        /*
         * All the children were made ok. Now youngestChild->mtime contains the
         * modification time of the newest child, we need to find out if we
         * exist and when we were modified last. The criteria for datedness
         * are defined by GNode_IsOODate.
         */
        DEBUG1(MAKE, "Examining %s...", gn->name);
        if (!GNode_IsOODate(gn)) {
                gn->made = UPTODATE;
                DEBUG0(MAKE, "up-to-date.\n");
                return false;
        }

        /*
         * If the user is just seeing if something is out-of-date, exit now
         * to tell him/her "yes".
         */
        DEBUG0(MAKE, "out-of-date.\n");
        if (opts.query && gn != Targ_GetEndNode())
                exit(1);

        /*
         * We need to be re-made.
         * Ensure that $? (.OODATE) and $> (.ALLSRC) are both set.
         */
        GNode_SetLocalVars(gn);

        /*
         * Alter our type to tell if errors should be ignored or things
         * should not be printed so Compat_RunCommand knows what to do.
         */
        if (opts.ignoreErrors)
                gn->type |= OP_IGNORE;
        if (opts.silent)
                gn->type |= OP_SILENT;

        if (Job_CheckCommands(gn, Fatal)) {
                if (!opts.touch || (gn->type & OP_MAKE)) {
                        curTarg = gn;
#ifdef USE_META
                        if (useMeta && GNode_ShouldExecute(gn))
                                meta_job_start(NULL, gn);
#endif
                        RunCommands(gn);
                        curTarg = NULL;
                } else {
                        Job_Touch(gn, (gn->type & OP_SILENT) != OP_NONE);
                }
        } else {
                gn->made = ERROR;
        }
#ifdef USE_META
        if (useMeta && GNode_ShouldExecute(gn)) {
                if (meta_job_finish(NULL) != 0)
                        gn->made = ERROR;
        }
#endif

        if (gn->made != ERROR) {
                /*
                 * If the node was made successfully, mark it so, update
                 * its modification time and timestamp all its parents.
                 * This is to keep its state from affecting that of its parent.
                 */
                gn->made = MADE;
                if (Make_Recheck(gn) == 0)
                        pgn->flags.force = true;
                if (!(gn->type & OP_EXEC)) {
                        pgn->flags.childMade = true;
                        GNode_UpdateYoungestChild(pgn, gn);
                }
        } else if (opts.keepgoing) {
                pgn->flags.remake = false;
        } else {
                PrintOnError(gn, "\nStop.\n");
                exit(1);
        }
        return true;
}

static void
MakeOther(GNode *gn, GNode *pgn)
{

        if (Lst_FindDatum(&gn->implicitParents, pgn) != NULL) {
                const char *target = GNode_VarTarget(gn);
                Var_Set(pgn, IMPSRC, target != NULL ? target : "");
        }

        switch (gn->made) {
        case BEINGMADE:
                Error("Graph cycles through %s", gn->name);
                gn->made = ERROR;
                pgn->flags.remake = false;
                break;
        case MADE:
                if (!(gn->type & OP_EXEC)) {
                        pgn->flags.childMade = true;
                        GNode_UpdateYoungestChild(pgn, gn);
                }
                break;
        case UPTODATE:
                if (!(gn->type & OP_EXEC))
                        GNode_UpdateYoungestChild(pgn, gn);
                break;
        default:
                break;
        }
}

/*
 * Make a target.
 *
 * If an error is detected and not being ignored, the process exits.
 *
 * Input:
 *      gn              The node to make
 *      pgn             Parent to abort if necessary
 *
 * Output:
 *      gn->made
 *              UPTODATE        gn was already up-to-date.
 *              MADE            gn was recreated successfully.
 *              ERROR           An error occurred while gn was being created,
 *                              either due to missing commands or in -k mode.
 *              ABORTED         gn was not remade because one of its
 *                              dependencies could not be made due to errors.
 */
void
Compat_Make(GNode *gn, GNode *pgn)
{
        if (shellName == NULL)  /* we came here from jobs */
                Shell_Init();

        if (gn->made == UNMADE && (gn == pgn || !(pgn->type & OP_MADE))) {
                if (!MakeUnmade(gn, pgn))
                        goto cohorts;

                /* XXX: Replace with GNode_IsError(gn) */
        } else if (gn->made == ERROR) {
                /*
                 * Already had an error when making this.
                 * Tell the parent to abort.
                 */
                pgn->flags.remake = false;
        } else {
                MakeOther(gn, pgn);
        }

cohorts:
        MakeNodes(&gn->cohorts, pgn);
}

static void
MakeBeginNode(void)
{
        GNode *gn = Targ_FindNode(".BEGIN");
        if (gn == NULL)
                return;

        Compat_Make(gn, gn);
        if (GNode_IsError(gn)) {
                PrintOnError(gn, "\nStop.\n");
                exit(1);
        }
}

static void
InitSignals(void)
{
        if (bmake_signal(SIGINT, SIG_IGN) != SIG_IGN)
                bmake_signal(SIGINT, CompatInterrupt);
        if (bmake_signal(SIGTERM, SIG_IGN) != SIG_IGN)
                bmake_signal(SIGTERM, CompatInterrupt);
        if (bmake_signal(SIGHUP, SIG_IGN) != SIG_IGN)
                bmake_signal(SIGHUP, CompatInterrupt);
        if (bmake_signal(SIGQUIT, SIG_IGN) != SIG_IGN)
                bmake_signal(SIGQUIT, CompatInterrupt);
}

void
Compat_MakeAll(GNodeList *targets)
{
        GNode *errorNode = NULL;

        if (shellName == NULL)
                Shell_Init();

        InitSignals();

        /*
         * Create the .END node now, to keep the (debug) output of the
         * counter.mk test the same as before 2020-09-23.  This
         * implementation detail probably doesn't matter though.
         */
        (void)Targ_GetEndNode();

        if (!opts.query)
                MakeBeginNode();

        /*
         * Expand .USE nodes right now, because they can modify the structure
         * of the tree.
         */
        Make_ExpandUse(targets);

        while (!Lst_IsEmpty(targets)) {
                GNode *gn = Lst_Dequeue(targets);
                Compat_Make(gn, gn);

                if (gn->made == UPTODATE) {
                        printf("`%s' is up to date.\n", gn->name);
                } else if (gn->made == ABORTED) {
                        printf("`%s' not remade because of errors.\n",
                            gn->name);
                }
                if (GNode_IsError(gn) && errorNode == NULL)
                        errorNode = gn;
        }

        if (errorNode == NULL) {
                GNode *endNode = Targ_GetEndNode();
                Compat_Make(endNode, endNode);
                if (GNode_IsError(endNode))
                        errorNode = endNode;
        }

        if (errorNode != NULL) {
                if (DEBUG(GRAPH2))
                        Targ_PrintGraph(2);
                else if (DEBUG(GRAPH3))
                        Targ_PrintGraph(3);
                PrintOnError(errorNode, "\nStop.\n");
                exit(1);
        }
}