/*-
 * Copyright (c) 2004, The DragonFly Project.  All rights reserved.
 * Copyright (c) 1998, Peter Wemm <peter@netplex.com.au>
 * All rights reserved.
 *
 * 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.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
 *
 * $FreeBSD: src/usr.bin/objformat/objformat.c,v 1.6 1998/10/24 02:01:30 jdp Exp $
 */

#include <err.h>
#include <limits.h> /* PATH_MAX */
#include <objformat.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

#ifndef CCVER_DEFAULT
#define CCVER_DEFAULT "gcc80"
#endif

#ifndef BINUTILSVER_DEFAULT
#define BINUTILSVER_DEFAULT "binutils234"
#endif

#define LINKER_BFD     "ld.bfd"
#define LINKER_GOLD    "ld.gold"
#define LINKER_DEFAULT LINKER_GOLD
#define LINKER_ALT     LINKER_BFD

#ifndef OBJFORMAT_PATH_DEFAULT
#define OBJFORMAT_PATH_DEFAULT ""
#endif

enum cmd_type { OBJFORMAT, COMPILER, BINUTILS, LINKER };

struct command {
        const char *cmd;
        enum cmd_type type;
};

static struct command commands[] = {
        {"CC",                  COMPILER},
        {"c++",                 COMPILER},
        {"cc",                  COMPILER},
        {"cpp",                 COMPILER},
        {"g++",                 COMPILER},
        {"gcc",                 COMPILER},
        {"gcov",                COMPILER},
        {"ld",                  LINKER},
        {"addr2line",           BINUTILS},
        {"ar",                  BINUTILS},
        {"as",                  BINUTILS},
        {"c++filt",             BINUTILS},
        {"elfedit",             BINUTILS},
        {"gprof",               BINUTILS},
        {"ld.bfd",              BINUTILS},
        {"ld.gold",             BINUTILS},
        {"nm",                  BINUTILS},
        {"objcopy",             BINUTILS},
        {"objdump",             BINUTILS},
        {"ranlib",              BINUTILS},
        {"readelf",             BINUTILS},
        {"size",                BINUTILS},
        {"strings",             BINUTILS},
        {"strip",               BINUTILS},
        {"objformat",           OBJFORMAT},
        {NULL,                  -1},
};

int
main(int argc, char **argv)
{
        const char *base_path = "/usr/libexec";
        char ld_def[] = LINKER_DEFAULT;
        char ld_alt[] = LINKER_ALT;
        struct command *cmds;
        char objformat[32];
        char newcmd[PATH_MAX];
        char *path, *chunk;
        char *cmd;
        char *ldcmd = ld_def;
        const char *objformat_path;
        const char *ccver;
        const char *buver;
        const char *ldver;
        const char *env_value = NULL;
        int use_objformat = 0;

        if (getobjformat(objformat, sizeof objformat, &argc, argv) == -1)
                errx(1, "Invalid object format");

        /*
         * Get the last path element of the program name being executed
         */
        cmd = strrchr(argv[0], '/');
        if (cmd != NULL)
                cmd++;
        else
                cmd = argv[0];

        for (cmds = commands; cmds->cmd != NULL; ++cmds) {
                if (strcmp(cmd, cmds->cmd) == 0)
                        break;
        }

        switch (cmds->type) {
        case COMPILER:
                ccver = getenv("CCVER");
                if ((ccver == NULL) || ccver[0] == 0)
                        ccver = CCVER_DEFAULT;
                use_objformat = 0;
                env_value = ccver;
                break;
        case BINUTILS:
                buver = getenv("BINUTILSVER");
                if (buver == NULL)
                        buver = BINUTILSVER_DEFAULT;
                use_objformat = 1;
                env_value = buver;
                break;
        case LINKER:
                buver = getenv("BINUTILSVER");
                if (buver == NULL)
                        buver = BINUTILSVER_DEFAULT;
                ldver = getenv("LDVER");
                if ((ldver != NULL) && (strcmp(ldver, ld_alt) == 0))
                        ldcmd = ld_alt;
                use_objformat = 1;
                env_value = buver;
                cmd = ldcmd;
                break;
        case OBJFORMAT:
                break;
        default:
                errx(1, "unknown command type");
                break;
        }

        /*
         * The objformat command itself doesn't need another exec
         */
        if (cmds->type == OBJFORMAT) {
                if (argc != 1) {
                        fprintf(stderr, "Usage: objformat\n");
                        exit(1);
                }

                printf("%s\n", objformat);
                exit(0);
        }

        if (setenv("OBJFORMAT", objformat, 1) == -1)
                err(1, "setenv: cannot set OBJFORMAT=%s", objformat);

        /*
         * make buildworld glue and CCVER overrides.
         */
        objformat_path = getenv("OBJFORMAT_PATH");
        if (objformat_path == NULL)
                objformat_path = OBJFORMAT_PATH_DEFAULT;

again:
        path = strdup(objformat_path);

        /*
         * objformat_path could be sequence of colon-separated paths.
         */
        while ((chunk = strsep(&path, ":")) != NULL) {
                if (use_objformat) {
                        snprintf(newcmd, sizeof(newcmd), "%s%s/%s/%s/%s",
                                chunk, base_path, env_value, objformat, cmd);
                } else {
                        snprintf(newcmd, sizeof(newcmd), "%s%s/%s/%s",
                                chunk, base_path, env_value, cmd);
                }

                argv[0] = newcmd;
                execv(newcmd, argv);
        }

        /*
         * Fallback: if we're searching for a compiler, but didn't find any,
         * try again using the custom compiler driver to access the external
         * compilers defined by compilers.conf(5).
         */
        if (cmds->type == COMPILER && strcmp(env_value, "custom") != 0) {
                env_value = "custom";
                goto again;
        }

        if (use_objformat) {
                err(1, "in path [%s]%s/%s/%s/%s",
                        objformat_path, base_path, env_value, objformat, cmd);
        } else {
                err(1, "in path [%s]%s/%s/%s",
                        objformat_path, base_path, env_value, cmd);
        }
}