/************************************************************************
 *
 * cmdopt.cpp - Definitions of the option parsing subsystem
 *
 * $Id$
 *
 ************************************************************************
 *
 * Licensed to the Apache Software  Foundation (ASF) under one or more
 * contributor  license agreements.  See  the NOTICE  file distributed
 * with  this  work  for  additional information  regarding  copyright
 * ownership.   The ASF  licenses this  file to  you under  the Apache
 * License, Version  2.0 (the  "License"); you may  not use  this file
 * except in  compliance with the License.   You may obtain  a copy of
 * the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the  License is distributed on an  "AS IS" BASIS,
 * WITHOUT  WARRANTIES OR CONDITIONS  OF ANY  KIND, either  express or
 * implied.   See  the License  for  the  specific language  governing
 * permissions and limitations under the License.
 *
 **************************************************************************/

/* disable Compaq/HP C++ pure libc headers to allow POSIX symbols
   such as SIGALRM or SIGKILL to be defined.*/
#undef __PURE_CNAME

#include <assert.h> /* for assert() */
#include <ctype.h> /* for isspace */
#include <errno.h> /* for errno */
#include <signal.h> /* for raise, signal, SIG_IGN */
#include <stdio.h> /* for *printf, fputs */
#include <stdlib.h> /* for exit */
#include <string.h> /* for str* */
#ifndef _WIN32
#  include <unistd.h> /* for sleep */

#  if defined (_XOPEN_UNIX)
#    include <sys/resource.h> /* for struct rlimit, RLIMIT_CORE, ... */
#  endif

#else
#  include <windows.h> /* for Sleep */
#endif   /* _WIN32 */

#include "exec.h"
#include "target.h"
#include "util.h"

#include "cmdopt.h"

const char* exe_name; /**< Alias for process argv [0]. */

#ifndef _WIN32

const char escape_code = '\\';
const char default_path_sep = '/';
const char suffix_sep = '.';
const size_t exe_suffix_len = 0;

#else   /* Win32 */

const char escape_code = '^';
const char default_path_sep = '\\';
const char suffix_sep = '.';
const size_t exe_suffix_len = 4; /* strlen(".exe") == 4 */

#  ifndef _WIN32_WINNT
#    define _WIN32_WINNT 0x0500
#  endif

#  if _WIN32_WINNT >= 0x0500
#    define RLIMIT_AS
#  endif
#endif

static const char
usage_text[] = {
    "Usage: %s [OPTIONS] [targets]\n"
    "\n"
    "  Treats each token in targets as the path to an executable. Each target\n"
    "  enumerated is executed, and the output is processed after termination.\n"
    "  If target prepended by '@' character, target is treated as text file\n"
    "  with list of targets (one target per line).\n"
    "  If the execution takes longer than a certain (configurable) amount of\n"
    "  time, the process is killed.\n"
    "\n"
    "    -d dir       Specify root directory for output reference files.\n"
    "    -h, -?       Display usage information and exit.\n"
    "    -t seconds   Set timeout before killing target (default is 10\n"
    "                 seconds).\n"
    "    -x opts      Specify command line options to pass to targets.\n"
    "    --           Terminate option processing and treat all arguments\n"
    "                 that follow as targets.\n"
    "    --compat     Use compatability mode test output parsing.\n"
    "    --nocompat   Use standard test output parsing (default).\n"
    "    --help       Display usage information and exit.\n"
    "    --exit=val   Exit immediately with the specified return code.\n"
    "    --sleep=sec  Sleep for the specified number of seconds.\n"
    "    --signal=sig Send itself the specified signal.\n"
    "    --ignore=sig Ignore the specified signal.\n"
    "    --ulimit=lim Set child process usage limits (see below).\n"
    "    --warn=alias Set compiler log warning pattern (see below).\n"
    "\n"
    "  All short (single dash) options must be specified seperately.\n"
    "  If a short option takes a value, it may either be provided like\n"
    "  '-sval' or '-s val'.\n"
    "  If a long option take a value, it may either be provided like\n"
    "  '--option=value' or '--option value'.\n"
    "\n"
    "  --ulimit sets limits on how much of a given resource or resorces\n"
    "  child processes are allowed to utilize.  These limits take on two\n"
    "  forms, 'soft' and 'hard' limits.  Options are specified in the form\n"
    "  'resource:limit', where resource is a resource named below, and and\n"
    "  limit is a number, with value specifing the limit for the named\n"
    "  resource.  If multiple limits are to be set, they can be specified\n"
    "  either in multiple instances of the --ulimit switch, or by specifying\n"
    "  additional limits in the same call by seperating the pairs with\n"
    "  commas.  'Soft' limits are specified by providing the resource name\n"
    "  in lowercase letters, while 'hard' limits are specified by providing\n"
    "  the resource name in uppercase letters.  To set both limits, specify\n"
    "  the resource name in title case.\n"
    "\n"
    "  --ulimit modes:\n"
    "    core   Maximum size of core file, in bytes.\n"
    "    cpu    Maximum CPU time, in seconds.\n"
    "    data   Maximum data segment size, in bytes.\n"
    "    fsize  Maximum size of generated files, in bytes.\n"
    "    nofile Maximum number of open file descriptors.\n"
    "    stack  Maximum size of initial thread's stack, in bytes.\n"
    "    as     Maximum size of available memory, in bytes.\n"
    "\n"
    "  Note: Some operating systems lack support for some or all of the\n"
    "  ulimit modes.  If a system is unable to limit a given property, a\n"
    "  warning message will be produced.\n"
    "\n"
    "  --warn set the string used to parse compile and link logs.  Rather\n"
    "  than specifying a search string, an alias code is provided,\n"
    "  coresponding to the output of a compiler and linker.  Alias codes\n"
    "  are case sensitive.\n"
    "\n"
    "  --warn modes:\n"
    "    acc     HP aCC\n"
    "    cxx     Compaq C++\n"
    "    eccp    EDG eccp\n"
    "    gcc     GNU gcc\n"
    "    icc     Intel icc for Linux\n"
    "    mipspro SGI MIPSpro\n"
    "    sunpro  Sun C++\n"
    "    vacpp   IBM VisualAge C++\n"
    "    xlc     IBM XLC++\n"
};


/**
   Display command line switches for program and terminate.

   @param status status code to exit with.
*/
static void 
show_usage (int status)
{
    FILE* const where = status ? stderr : stdout;

    assert (0 != exe_name);

    fprintf (where, usage_text, exe_name);

    exit (status);
}

/**
    Helper function to read the value for a short option
    
    @param argv argument array
    @param idx reference to index for option
*/
static char*
get_short_val (char* const* argv, int* idx)
{
    assert (0 != argv);
    assert (0 != idx);

    if ('\0' == argv [*idx][2])
        return argv [++(*idx)];
    else
        return argv [*idx] + 2;
}

/**
    Helper function to read the value for a long option
    
    @param argv argument array
    @param idx reference to index for option
    @param offset length of option name (including leading --)
*/
static char*
get_long_val (char* const* argv, int* idx, size_t offset)
{
    assert (0 != argv);
    assert (0 != idx);

    if ('\0' == argv [*idx][offset])
        return argv [++(*idx)];
    else if ('=' == argv [*idx][offset])
        return argv [*idx] + offset + 1;
    else
        return (char*)0;
}

/**
   Helper function to parse a ulimit value string

   @param opts ulimit value string to pares
   @see child_limits
*/
static bool
parse_limit_opts (const char* opts, struct target_opts* defaults)
{
    static const struct {
        rw_rlimit** limit;
        const char* name;
        const char* caps;
        const char* mixd;
        size_t len;
    } limits[] = {
        {
#ifdef RLIMIT_CORE
            &defaults->core,
#else
            0,
#endif   /* RLIMIT_CORE */
            "core", "CORE", "Core", 4 },
        {
#ifdef RLIMIT_CPU
            &defaults->cpu,
#else
            0,
#endif   /* RLIMIT_CPU */
            "cpu", "CPU", "Cpu", 3 },
        {
#ifdef RLIMIT_DATA
            &defaults->data,
#else
            0,
#endif   /* RLIMIT_DATA */
            "data", "DATA", "Data", 4 },
        {
#ifdef RLIMIT_FSIZE
            &defaults->fsize,
#else
            0,
#endif   /* RLIMIT_FSIZE */
            "fsize", "FSIZE", "Fsize", 5 },
        {
#ifdef RLIMIT_NOFILE
            &defaults->nofile,
#else
            0,
#endif   /* RLIMIT_NOFILE */
            "nofile", "NOFILE", "Nofile", 6 },
        {
#ifdef RLIMIT_STACK
            &defaults->stack,
#else
            0,
#endif   /* RLIMIT_STACK */
            "stack", "STACK", "Stack", 5 },
        {
#ifdef RLIMIT_AS
            &defaults->as,
#else
            0,
#endif   /* RLIMIT_AS */    
            "as", "AS", "As", 2 },
        { 0, 0, 0, 0, 0 }
    };

    const char* arg = opts;

    assert (0 != opts);

    while (arg && *arg) {

        const size_t arglen = strlen (arg);

        for (size_t i = 0; limits [i].name; ++i) {
            if (   limits [i].len < arglen
                && (   0 == memcmp (limits [i].name, arg, limits [i].len)
                    || 0 == memcmp (limits [i].caps, arg, limits [i].len)
                    || 0 == memcmp (limits [i].mixd, arg, limits [i].len))
                && ':' == arg [limits [i].len]) {

                /* determine whether the hard limit and/or the soft limit
                   should be set. */
                const bool hard = 0 != isupper (arg [0]);
                const bool soft = 0 != islower (arg [1]);

                arg += limits [i].len + 1;

                if (!isdigit (*arg)) {
                    return 1;
                }

                char *end;
                const long lim = strtol (arg, &end, 10);

                arg = end;

                if ('\0' != *arg && ',' != *arg)
                    break;

                if (limits [i].limit) {
                    if (!*limits [i].limit) {
                        (*limits [i].limit) = 
                            (rw_rlimit*)RW_MALLOC (sizeof (rw_rlimit));
                        (*limits [i].limit)->rlim_cur = RLIM_SAVED_CUR;
                        (*limits [i].limit)->rlim_max = RLIM_SAVED_MAX;
                    }
                    if (soft)
                        (*limits [i].limit)->rlim_cur = lim;

                    if (hard)
                        (*limits [i].limit)->rlim_max = lim;
                }
                else
                    warn ("Unable to process %s limit: Not supported\n", 
                          limits [i].name);
                break;
            }
        }

        if (',' == *arg) {
            ++arg;
        }
        else if ('\0' != *arg) {
            return 1;
        }
    }
    return 0;
}

/**
   Helper function to parse a warning value string

   @param opts ulimit value string to pares
   @see child_limits
*/
static bool
parse_warn_opts (const char* arg, struct target_opts* defaults)
{
    static const struct {
        const char* name;
        const char* pat;
    } warn_set [] = {
        { "acc", "Warning " },
/*
        { "cds", "UNKNOWN"},
        { "como", "UNKNOWN"},
*/
        { "cxx", "Warning:"},
        { "eccp", "warning:"},
        { "gcc", "warning:"},
        { "icc", "warning #"},
        { "mipspro", "CC: WARNING"},
        { "sunpro", "Warning:"},
        { "vacpp", ": (W) "},
        { "xlc", ": (W) "}, /* xlc and vacpp are synonyms. */
        { 0, 0 }
    };

    assert (0 != arg);
    assert (0 != defaults);

    for (size_t i = 0; warn_set [i].name; ++i) {
        if (0 == strcmp (warn_set [i].name, arg)) {

            /* Set both compiler and linker warning string. */
            defaults->c_warn = warn_set [i].pat;
            defaults->l_warn = warn_set [i].pat;

            return 0;
        }
    }

    return 1;
}

/**
    Helper function to produce 'Bad argument' error message.
    
    @param opt name of option encountered
    @param val invalid value found
*/
static void
bad_value (const char* opt, const char* val)
{
    assert (0 != opt);

    terminate (1, "Bad argument for %s: %s\n", opt, val);
}

/**
    Helper function to produce 'Missing argument' error message.
    
    @param opt name of option missing argument
*/
static void
missing_value (const char* opt)
{
    assert (0 != opt);

    terminate (1, "Missing argument for %s\n", opt);
}

/**
    Helper function to produce 'Unknown option' error message.
    
    @param opt name of option encountered
*/
static void
bad_option (const char* opt)
{
    assert (0 != opt);

    warn ("Unknown option: %s\n", opt);

    show_usage (1);
}

int 
eval_options (int argc, char **argv, struct target_opts* defaults, 
              const char** exe_opts)
{
    const char opt_timeout[]  = "-t";
    const char opt_data_dir[] = "-d";
    const char opt_t_flags[]  = "-x";
    const char opt_compat[]   = "--compat";
    const char opt_exit[]     = "--exit";
    const char opt_help[]     = "--help";
    const char opt_ignore[]   = "--ignore";
    const char opt_nocompat[] = "--nocompat";
    const char opt_signal[]   = "--signal";
    const char opt_sleep[]    = "--sleep";
    const char opt_ulimit[]   = "--ulimit";
    const char opt_verbose[]  = "--verbose";
    const char opt_warn[]     = "--warn";

    int i;

    assert (0 != argv);
    assert (0 != defaults);

    memset (defaults, 0, sizeof (target_opts));

    /* The chain of preprocesor logic below initializes the defaults->c_warn 
       and defaults->l_warn values.
    */
#ifdef __GNUG__
    parse_warn_opts ("Gcc", defaults);
#elif defined (__HP_aCC)
    parse_warn_opts ("Acc", defaults);
#elif defined (__IBMCPP__)
    parse_warn_opts ("Xlc", defaults);
#elif defined (__SUNPRO_CC)
    parse_warn_opts ("Sunpro", defaults);
#elif defined (SNI)
    parse_warn_opts ("Cds", defaults);
#elif defined (__APOGEE__) /* EDG variant that doesn't define __EDG__. */
    parse_warn_opts ("Como", defaults);

/* The following are EDG variants, that define __EDG__ */
#elif defined (__DECCXX)
    parse_warn_opts ("Cxx", defaults);
#elif defined (_SGI_COMPILER_VERSION)
    parse_warn_opts ("Mipspro", defaults);
#elif defined (__INTEL_COMPILER)
    parse_warn_opts ("Icc", defaults);

/* So we need to check for __EDG__ after we check for them. */
#elif defined (__EDG__)
    parse_warn_opts ("Eccp", defaults);
#endif

    if (1 == argc || '-' != argv [1][0])
        return 1;

    for (i = 1; i < argc && '-' == argv [i][0]; ++i) {

        /* the name of the option being processed */
        const char* optname = argv [i];

        /* the option's argument, if any */
        const char* optarg  = 0;

        char* end = 0;

        switch (argv [i][1]) {
        case '?':   /* display help and exit with status of 0 */
        case 'h':
            show_usage (0);

        case 'r':
            ++i; /* Ignore -r option (makefile compat) */
            break;

        case 't':   /* executable timeout in seconds */
            optname = opt_timeout;
            optarg  = get_short_val (argv, &i);
            if (optarg) {
                if (!isdigit (*optarg))
                    bad_value (optname, optarg);

                errno = 0;
                defaults->timeout = unsigned (strtol (optarg, &end, 10));
                if (*end || errno)
                    bad_value (optname, optarg);
            }
            else
                missing_value (optname);

            break;

        case 'd':   /* directory containing example reference files */
            optname = opt_data_dir;
            defaults->data_dir = get_short_val (argv, &i);
            if (!defaults->data_dir)
                missing_value (optname);
            break;

        case 'v':   /* enable verbose mode */
            optname = opt_verbose;
            ++defaults->verbose;
            break;

        case 'x':   /* command line options to pass to targets */
            optname  = opt_t_flags;
            *exe_opts = get_short_val (argv, &i);
            if (!*exe_opts)
                missing_value (optname);
            break;

        case '-':   /* long options */
        {
            const size_t arglen = strlen (argv [i]);

            /* abort processing on --, eat token */
            if ('\0' == argv [i][2])
                return i+1;

            if (   sizeof opt_compat - 1 == arglen
                && !memcmp (opt_compat, argv [i], sizeof opt_compat)) {
                /* enter compatibility mode */
                defaults->compat = 1;
                break;
            }
            else if (   sizeof opt_nocompat - 1 == arglen
                     && !memcmp (opt_nocompat, argv [i], sizeof opt_nocompat)) {
                /* exit compatibility mode */
                defaults->compat = 0;
                break;
            }
            else if (   sizeof opt_exit - 1 <= arglen
                     && !memcmp (opt_exit, argv [i], sizeof opt_exit - 1)) {
                /* exit immediately with the specified status */
                optname = opt_exit;
                optarg  = get_long_val (argv, &i, sizeof opt_exit - 1);
                if (optarg && *optarg) {
                    if (!isdigit (*optarg))
                        bad_value (optname, optarg);

                    errno = 0;
                    const long code = strtol (optarg, &end, 10);
                    if ('\0' == *end && !errno)
                        exit (int (code));
                }
            }
            else if (   sizeof opt_help - 1 == arglen
                     && !memcmp (opt_help, argv [i], sizeof opt_help - 1)) {
                /* display help and exit with status of 0 */
                optname = opt_help;
                show_usage (0);
                break;
            }
            else if (   sizeof opt_sleep - 1 <= arglen
                     && !memcmp (opt_sleep, argv [i], sizeof opt_sleep - 1)) {
                /* sleep for the specified number of seconds */ 
                optname = opt_sleep;
                optarg  = get_long_val (argv, &i, sizeof opt_sleep - 1);
                if (optarg && *optarg) {
                    if (!isdigit (*optarg))
                        bad_value (optname, optarg);

                    errno = 0;
                    const long nsec = strtol (optarg, &end, 10);
                    if ('\0' == *end && 0 <= nsec && !errno) {
                        rw_sleep (int (nsec));
                        break;
                    }
                }
            }
            else if (   sizeof opt_signal - 1 <= arglen
                     && !memcmp (opt_signal, argv [i], sizeof opt_signal - 1)) {
                /* send ourselves the specified signal */
                optname = opt_signal;
                optarg  = get_long_val (argv, &i, sizeof opt_signal - 1);
                if (optarg && *optarg) {
                    const int signo = get_signo (optarg);
                    if (0 <= signo) {
                        if (0 > raise (signo))
                            terminate (1, "raise(%s) failed: %s\n",
                                       get_signame (signo), strerror (errno));
                        break;
                    }
                }
            }
            else if (   sizeof opt_ignore - 1 <= arglen
                     && !memcmp (opt_ignore, argv [i], sizeof opt_ignore - 1)) {
                /* ignore the specified signal */
                optname = opt_ignore;
                optarg  = get_long_val (argv, &i, sizeof opt_ignore - 1);
                if (optarg && *optarg) {
                    const int signo = get_signo (optarg);
                    if (0 <= signo) {
                        if (rw_signal (signo, 0 /* SIG_IGN */))
                            terminate (1, "rw_signal(%s, ...) failed: %s\n",
                                       get_signame (signo), strerror (errno));
                        break;
                    }
                }
            }
            else if (   sizeof opt_ulimit - 1 <= arglen
                     && !memcmp (opt_ulimit, argv [i], sizeof opt_ulimit - 1)) {
                /* set child process resource utilization limits */
                optname = opt_ulimit;
                optarg  = get_long_val (argv, &i, sizeof opt_ulimit - 1);
                if (optarg && *optarg) {
                    if (!parse_limit_opts (optarg, defaults)) {
                        break;
                    }
                }
            }
            else if (   sizeof opt_warn - 1 <= arglen
                     && !memcmp (opt_warn, argv [i], sizeof opt_warn - 1)) {
                /* set compiler warning mode */
                optname = opt_warn;
                optarg  = get_long_val (argv, &i, sizeof opt_warn - 1);
                if (optarg && *optarg) {
                    if (!parse_warn_opts (optarg, defaults)) {
                        break;
                    }
                }
            }
            /* fall through */
        }
        default:
            if (optarg) {
                if (*optarg)
                    bad_value (optname, optarg);
                else
                    missing_value (optname);
            }

            if (argv [i])
                bad_option (argv [i]);
            else
                missing_value (optname);
        }
    }

    return i;
}

char**
split_opt_string (const char* opts)
{
    char in_quote = 0;
    int in_escape = 0;
    int in_token = 0;
    const char *pos;
    char *target, *last;
    char **table_pos, **argv;
    size_t optlen;

    assert (0 != opts);

    optlen = strlen (opts);

    if (0 == optlen) {
        /* Alloc a an index array to hold the program name  */
        argv = (char**)RW_MALLOC (sizeof (char*));

        /* And tie the two together */
        argv [0] = (char*)0;
        return argv;
    }

    table_pos = argv = (char**)RW_MALLOC ((optlen + 3) * sizeof (char*) / 2);
    /* (strlen (opts)+3)/2 is overkill for the most situations, but it is just 
       large enough to handle the worst case scenario.  The worst case is a 
       string similar to 'x y' or 'x y z', requiring array lengths of 4 and 5 
       respectively.
    */

    last = target = argv [0] = (char*)RW_MALLOC (optlen + 1);

    /* Transcribe the contents, handling escaping and splitting */
    for (pos = opts; *pos; ++pos) {
        if (in_escape) {
            *(target++) = *pos;
            in_escape = 0;
            continue;
        }
        if (isspace (*pos)) {
            if (in_quote) {
                *(target++) = *pos;
            }
            else {
                if (in_token) {
                    *(target++) = '\0';
                    *(table_pos++) = last;
                    in_token = 0;
                }
                last = target;
            }
            continue;
        }
        in_token = 1;
        switch (*pos) {
        case escape_code:
            in_escape = 1;
            break;
        case '"':
        case '\'':
            if (*pos == in_quote) {
                in_quote = 0;
                break;
            }
            else if (0 == in_quote) {
                in_quote = *pos;
                break;
            }
            /* intentionally falling through (in a quote and quote didn't 
               match opening quote.
            */
        default:
            *(target++) = *pos;
        }
    }

    if (in_token) { /* close and record the final token */
        *(target++) = '\0';
        *(table_pos++) = last;
    }
    *table_pos = (char*)0;/*And terminate the array*/

    return argv;
}