ptools/pargs/pargs.c

	pargs.c revision ba5fdd2d4d97ae03a892c1bd5557eafb030984d1
/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright 2007 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */
/*
 * Copyright (c) 2013, Joyent, Inc.  All rights reserved.
 */

/*
 * pargs examines and prints the arguments (argv), environment (environ),
 * and auxiliary vector of another process.
 *
 * This utility is made more complex because it must run in internationalized
 * environments.  The two key cases for pargs to manage are:
 *
 * 1. pargs and target run in the same locale: pargs must respect the
 * locale, but this case is straightforward.  Care is taken to correctly
 * use wide characters in order to print results properly.
 *
 * 2. pargs and target run in different locales: in this case, pargs examines
 * the string having assumed the victim's locale.  Unprintable (but valid)
 * characters are escaped.  Next, iconv(3c) is used to convert between the
 * target and pargs codeset.  Finally, a second pass to escape unprintable
 * (but valid) characters is made.
 *
 * In any case in which characters are encountered which are not valid in
 * their purported locale, the string "fails" and is treated as a traditional
 * 7-bit ASCII encoded string, and escaped accordingly.
 */

#include <stdio.h>
#include <stdlib.h>
#include <locale.h>
#include <wchar.h>
#include <iconv.h>
#include <langinfo.h>
#include <unistd.h>
#include <ctype.h>
#include <fcntl.h>
#include <string.h>
#include <strings.h>
#include <limits.h>
#include <pwd.h>
#include <grp.h>
#include <errno.h>
#include <setjmp.h>
#include <sys/types.h>
#include <sys/auxv.h>
#include <sys/archsystm.h>
#include <sys/proc.h>
#include <sys/elf.h>
#include <libproc.h>
#include <wctype.h>
#include <widec.h>
#include <elfcap.h>

typedef struct pargs_data {
    struct ps_prochandle *pd_proc;  /* target proc handle */
    psinfo_t *pd_psinfo;        /* target psinfo */
    char *pd_locale;        /* target process locale */
    int pd_conv_flags;      /* flags governing string conversion */
    iconv_t pd_iconv;       /* iconv conversion descriptor */
    size_t pd_argc;
    uintptr_t *pd_argv;
    char **pd_argv_strs;
    size_t pd_envc;
    uintptr_t *pd_envp;
    char **pd_envp_strs;
    size_t pd_auxc;
    auxv_t *pd_auxv;
    char **pd_auxv_strs;
    char *pd_execname;
} pargs_data_t;

#define CONV_USE_ICONV      0x01
#define CONV_STRICT_ASCII   0x02

static char *command;
static int dmodel;

#define EXTRACT_BUFSZ 128       /* extract_string() initial size */
#define ENV_CHUNK 16            /* #env ptrs to read at a time */

static jmp_buf env;         /* malloc failure handling */

static void *
safe_zalloc(size_t size)
{
    void *p;

    /*
     * If the malloc fails we longjmp out to allow the code to Prelease()
     * a stopped victim if needed.
     */
    if ((p = malloc(size)) == NULL) {
        longjmp(env, errno);
    }

    bzero(p, size);
    return (p);
}

static char *
safe_strdup(const char *s1)
{
    char    *s2;

    s2 = safe_zalloc(strlen(s1) + 1);
    (void) strcpy(s2, s1);
    return (s2);
}

/*
 * Given a wchar_t which might represent an 'escapable' sequence (see
 * formats(5)), return the base ascii character needed to print that
 * sequence.
 *
 * The comparisons performed may look suspect at first, but all are valid;
 * the characters below all appear in the "Portable Character Set."  The
 * Single Unix Spec says: "The wide-character value for each member of the
 * Portable Character Set will equal its value when used as the lone
 * character in an integer character constant."
 */
static uchar_t
get_interp_char(wchar_t wc)
{
    switch (wc) {
    case L'\a':
        return ('a');
    case L'\b':
        return ('b');
    case L'\f':
        return ('f');
    case L'\n':
        return ('n');
    case L'\r':
        return ('r');
    case L'\t':
        return ('t');
    case L'\v':
        return ('v');
    case L'\\':
        return ('\\');
    }
    return ('\0');
}

static char *
unctrl_str_strict_ascii(const char *src, int escape_slash, int *unprintable)
{
    uchar_t *uc, *ucp, c, ic;
    uc = ucp = safe_zalloc((strlen(src) * 4) + 1);
    while ((c = *src++) != '\0') {
        /*
         * Call get_interp_char *first*, since \ will otherwise not
         * be escaped as \\.
         */
        if ((ic = get_interp_char((wchar_t)c)) != '\0') {
            if (escape_slash || ic != '\\')
                *ucp++ = '\\';
            *ucp++ = ic;
        } else if (isascii(c) && isprint(c)) {
            *ucp++ = c;
        } else {
            *ucp++ = '\\';
            *ucp++ = ((c >> 6) & 7) + '0';
            *ucp++ = ((c >> 3) & 7) + '0';
            *ucp++ = (c & 7) + '0';
            *unprintable = 1;
        }
    }
    *ucp = '\0';
    return ((char *)uc);
}

/*
 * Convert control characters as described in format(5) to their readable
 * representation; special care is taken to handle multibyte character sets.
 *
 * If escape_slash is true, escaping of '\' occurs.  The first time a string
 * is unctrl'd, this should be '1'.  Subsequent iterations over the same
 * string should set escape_slash to 0.  Otherwise you'll wind up with
 * \ --> \\ --> \\\\.
 */
static char *
unctrl_str(const char *src, int escape_slash, int *unprintable)
{
    wchar_t wc;
    wchar_t *wide_src, *wide_srcp;
    wchar_t *wide_dest, *wide_destp;
    char *uc;
    size_t srcbufsz = strlen(src) + 1;
    size_t destbufsz = srcbufsz * 4;
    size_t srclen, destlen;

    wide_srcp = wide_src = safe_zalloc(srcbufsz * sizeof (wchar_t));
    wide_destp = wide_dest = safe_zalloc(destbufsz * sizeof (wchar_t));

    if ((srclen = mbstowcs(wide_src, src, srcbufsz - 1)) == (size_t)-1) {
        /*
         * We can't trust the string, since in the locale in which
         * this call is operating, the string contains an invalid
         * multibyte sequence.  There isn't much to do here, so
         * convert the string byte by byte to wide characters, as
         * if it came from a C locale (char) string.  This isn't
         * perfect, but at least the characters will make it to
         * the screen.
         */
        free(wide_src);
        free(wide_dest);
        return (unctrl_str_strict_ascii(src, escape_slash,
            unprintable));
    }
    if (srclen == (srcbufsz - 1)) {
        wide_src[srclen] = L'\0';
    }

    while ((wc = *wide_srcp++) != L'\0') {
        char cvt_buf[MB_LEN_MAX];
        int len, i;
        char c = get_interp_char(wc);

        if ((c != '\0') && (escape_slash || c != '\\')) {
            /*
             * Print "interpreted version" (\n, \a, etc).
             */
            *wide_destp++ = L'\\';
            *wide_destp++ = (wchar_t)c;
            continue;
        }

        if (iswprint(wc)) {
            *wide_destp++ = wc;
            continue;
        }

        /*
         * Convert the wide char back into (potentially several)
         * multibyte characters, then escape out each of those bytes.
         */
        bzero(cvt_buf, sizeof (cvt_buf));
        if ((len = wctomb(cvt_buf, wc)) == -1) {
            /*
             * This is a totally invalid wide char; discard it.
             */
            continue;
        }
        for (i = 0; i < len; i++) {
            uchar_t c = cvt_buf[i];
            *wide_destp++ = L'\\';
            *wide_destp++ = (wchar_t)('0' + ((c >> 6) & 7));
            *wide_destp++ = (wchar_t)('0' + ((c >> 3) & 7));
            *wide_destp++ = (wchar_t)('0' + (c & 7));
            *unprintable = 1;
        }
    }

    *wide_destp = '\0';
    destlen = (wide_destp - wide_dest) * MB_CUR_MAX + 1;
    uc = safe_zalloc(destlen);
    if (wcstombs(uc, wide_dest, destlen) == (size_t)-1) {
        /* If we've gotten this far, wcstombs shouldn't fail... */
        (void) fprintf(stderr, "%s: wcstombs failed unexpectedly: %s\n",
            command, strerror(errno));
        exit(1);
    } else {
        char *tmp;
        /*
         * Try to save memory; don't waste 3 * strlen in the
         * common case.
         */
        tmp = safe_strdup(uc);
        free(uc);
        uc = tmp;
    }
    free(wide_dest);
    free(wide_src);
    return (uc);
}

/*
 * These functions determine which characters are safe to be left unquoted.
 * Rather than starting with every printable character and subtracting out the
 * shell metacharacters, we take the more conservative approach of starting with
 * a set of safe characters and adding those few common punctuation characters
 * which are known to be safe.  The rules are:
 *
 *  If this is a printable character (graph), and not punctuation, it is
 *  safe to leave unquoted.
 *
 *  If it's one of known hard-coded safe characters, it's also safe to leave
 *  unquoted.
 *
 *  Otherwise, the entire argument must be quoted.
 *
 * This will cause some strings to be unecessarily quoted, but it is safer than
 * having a character unintentionally interpreted by the shell.
 */
static int
issafe_ascii(char c)
{
    return (isalnum(c) || strchr("_.-/@:,", c) != NULL);
}

static int
issafe(wchar_t wc)
{
    return ((iswgraph(wc) && !iswpunct(wc)) ||
        wschr(L"_.-/@:,", wc) != NULL);
}

/*ARGSUSED*/
static char *
quote_string_ascii(pargs_data_t *datap, char *src)
{
    char *dst;
    int quote_count = 0;
    int need_quote = 0;
    char *srcp, *dstp;
    size_t dstlen;

    for (srcp = src; *srcp != '\0'; srcp++) {
        if (!issafe_ascii(*srcp)) {
            need_quote = 1;
            if (*srcp == '\'')
                quote_count++;
        }
    }

    if (!need_quote)
        return (src);

    /*
     * The only character we care about here is a single quote.  All the
     * other unprintable characters (and backslashes) will have been dealt
     * with by unctrl_str().  We make the following subtitution when we
     * encounter a single quote:
     *
     *  ' = '"'"'
     *
     * In addition, we put single quotes around the entire argument.  For
     * example:
     *
     *  foo'bar = 'foo'"'"'bar'
     */
    dstlen = strlen(src) + 3 + 4 * quote_count;
    dst = safe_zalloc(dstlen);

    dstp = dst;
    *dstp++ = '\'';
    for (srcp = src; *srcp != '\0'; srcp++, dstp++) {
        *dstp = *srcp;

        if (*srcp == '\'') {
            dstp[1] = '"';
            dstp[2] = '\'';
            dstp[3] = '"';
            dstp[4] = '\'';
            dstp += 4;
        }
    }
    *dstp++ = '\'';
    *dstp = '\0';

    free(src);

    return (dst);
}

static char *
quote_string(pargs_data_t *datap, char *src)
{
    wchar_t *wide_src, *wide_srcp;
    wchar_t *wide_dest, *wide_destp;
    char *uc;
    size_t srcbufsz = strlen(src) + 1;
    size_t srclen;
    size_t destbufsz;
    size_t destlen;
    int quote_count = 0;
    int need_quote = 0;

    if (datap->pd_conv_flags & CONV_STRICT_ASCII)
        return (quote_string_ascii(datap, src));

    wide_srcp = wide_src = safe_zalloc(srcbufsz * sizeof (wchar_t));

    if ((srclen = mbstowcs(wide_src, src, srcbufsz - 1)) == (size_t)-1) {
        free(wide_src);
        return (quote_string_ascii(datap, src));
    }

    if (srclen == srcbufsz - 1)
        wide_src[srclen] = L'\0';

    for (wide_srcp = wide_src; *wide_srcp != '\0'; wide_srcp++) {
        if (!issafe(*wide_srcp)) {
            need_quote = 1;
            if (*wide_srcp == L'\'')
                quote_count++;
        }
    }

    if (!need_quote) {
        free(wide_src);
        return (src);
    }

    /*
     * See comment for quote_string_ascii(), above.
     */
    destbufsz = srcbufsz + 3 + 4 * quote_count;
    wide_destp = wide_dest = safe_zalloc(destbufsz * sizeof (wchar_t));

    *wide_destp++ = L'\'';
    for (wide_srcp = wide_src; *wide_srcp != L'\0';
        wide_srcp++, wide_destp++) {
        *wide_destp = *wide_srcp;

        if (*wide_srcp == L'\'') {
            wide_destp[1] = L'"';
            wide_destp[2] = L'\'';
            wide_destp[3] = L'"';
            wide_destp[4] = L'\'';
            wide_destp += 4;
        }
    }
    *wide_destp++ = L'\'';
    *wide_destp = L'\0';

    destlen = destbufsz * MB_CUR_MAX + 1;
    uc = safe_zalloc(destlen);
    if (wcstombs(uc, wide_dest, destlen) == (size_t)-1) {
        /* If we've gotten this far, wcstombs shouldn't fail... */
        (void) fprintf(stderr, "%s: wcstombs failed unexpectedly: %s\n",
            command, strerror(errno));
        exit(1);
    }

    free(wide_dest);
    free(wide_src);

    return (uc);
}


/*
 * Determine the locale of the target process by traversing its environment,
 * making only one pass for efficiency's sake; stash the result in
 * datap->pd_locale.
 *
 * It's possible that the process has called setlocale() to change its
 * locale to something different, but we mostly care about making a good
 * guess as to the locale at exec(2) time.
 */
static void
lookup_locale(pargs_data_t *datap)
{
    int i, j, composite = 0;
    size_t  len = 0;
    char    *pd_locale;
    char    *lc_all = NULL, *lang = NULL;
    char    *lcs[] = { NULL, NULL, NULL, NULL, NULL, NULL };
    static const char *cat_names[] = {
        "LC_CTYPE=",    "LC_NUMERIC=",  "LC_TIME=",
        "LC_COLLATE=",  "LC_MONETARY=", "LC_MESSAGES="
    };

    for (i = 0; i < datap->pd_envc; i++) {
        char *s = datap->pd_envp_strs[i];

        if (s == NULL)
            continue;

        if (strncmp("LC_ALL=", s, strlen("LC_ALL=")) == 0) {
            /*
             * Minor optimization-- if we find LC_ALL we're done.
             */
            lc_all = s + strlen("LC_ALL=");
            break;
        }
        for (j = 0; j <= _LastCategory; j++) {
            if (strncmp(cat_names[j], s,
                strlen(cat_names[j])) == 0) {
                lcs[j] = s + strlen(cat_names[j]);
            }
        }
        if (strncmp("LANG=", s, strlen("LANG=")) == 0) {
            lang = s + strlen("LANG=");
        }
    }

    if (lc_all && (*lc_all == '\0'))
        lc_all = NULL;
    if (lang && (*lang == '\0'))
        lang = NULL;

    for (i = 0; i <= _LastCategory; i++) {
        if (lc_all != NULL) {
            lcs[i] = lc_all;
        } else if (lcs[i] != NULL) {
            lcs[i] = lcs[i];
        } else if (lang != NULL) {
            lcs[i] = lang;
        } else {
            lcs[i] = "C";
        }
        if ((i > 0) && (lcs[i] != lcs[i-1]))
            composite++;

        len += 1 + strlen(lcs[i]);  /* 1 extra byte for '/' */
    }

    if (composite == 0) {
        /* simple locale */
        pd_locale = safe_strdup(lcs[0]);
    } else {
        /* composite locale */
        pd_locale = safe_zalloc(len + 1);
        (void) snprintf(pd_locale, len + 1, "/%s/%s/%s/%s/%s/%s",
            lcs[0], lcs[1], lcs[2], lcs[3], lcs[4], lcs[5]);
    }
    datap->pd_locale = pd_locale;
}

/*
 * Pull a string from the victim, regardless of size; this routine allocates
 * memory for the string which must be freed by the caller.
 */
static char *
extract_string(pargs_data_t *datap, uintptr_t addr)
{
    int size = EXTRACT_BUFSZ;
    char *result;

    result = safe_zalloc(size);

    for (;;) {
        if (Pread_string(datap->pd_proc, result, size, addr) < 0) {
            free(result);
            return (NULL);
        } else if (strlen(result) == (size - 1)) {
            free(result);
            size *= 2;
            result = safe_zalloc(size);
        } else {
            break;
        }
    }
    return (result);
}

/*
 * Utility function to read an array of pointers from the victim, adjusting
 * for victim data model; returns the number of bytes successfully read.
 */
static ssize_t
read_ptr_array(pargs_data_t *datap, uintptr_t offset, uintptr_t *buf,
    size_t nelems)
{
    ssize_t res;

    if (dmodel == PR_MODEL_NATIVE) {
        res = Pread(datap->pd_proc, buf, nelems * sizeof (uintptr_t),
            offset);
    } else {
        int i;
        uint32_t *arr32 = safe_zalloc(nelems * sizeof (uint32_t));

        res = Pread(datap->pd_proc, arr32, nelems * sizeof (uint32_t),
            offset);
        if (res > 0) {
            for (i = 0; i < nelems; i++)
                buf[i] = arr32[i];
        }
        free(arr32);
    }
    return (res);
}

/*
 * Extract the argv array from the victim; store the pointer values in
 * datap->pd_argv and the extracted strings in datap->pd_argv_strs.
 */
static void
get_args(pargs_data_t *datap)
{
    size_t argc = datap->pd_psinfo->pr_argc;
    uintptr_t argvoff = datap->pd_psinfo->pr_argv;
    int i;

    datap->pd_argc = argc;
    datap->pd_argv = safe_zalloc(argc * sizeof (uintptr_t));

    if (read_ptr_array(datap, argvoff, datap->pd_argv, argc) <= 0) {
        free(datap->pd_argv);
        datap->pd_argv = NULL;
        return;
    }

    datap->pd_argv_strs = safe_zalloc(argc * sizeof (char *));
    for (i = 0; i < argc; i++) {
        if (datap->pd_argv[i] == 0)
            continue;
        datap->pd_argv_strs[i] = extract_string(datap,
            datap->pd_argv[i]);
    }
}

/*ARGSUSED*/
static int
build_env(void *data, struct ps_prochandle *pr, uintptr_t addr, const char *str)
{
    pargs_data_t *datap = data;

    if (datap->pd_envp != NULL) {
        datap->pd_envp[datap->pd_envc] = addr;
        if (str == NULL)
            datap->pd_envp_strs[datap->pd_envc] = NULL;
        else
            datap->pd_envp_strs[datap->pd_envc] = strdup(str);
    }

    datap->pd_envc++;

    return (0);
}

static void
get_env(pargs_data_t *datap)
{
    struct ps_prochandle *pr = datap->pd_proc;

    datap->pd_envc = 0;
    (void) Penv_iter(pr, build_env, datap);

    datap->pd_envp = safe_zalloc(sizeof (uintptr_t) * datap->pd_envc);
    datap->pd_envp_strs = safe_zalloc(sizeof (char *) * datap->pd_envc);

    datap->pd_envc = 0;
    (void) Penv_iter(pr, build_env, datap);
}

/*
 * The following at_* routines are used to decode data from the aux vector.
 */

/*ARGSUSED*/
static void
at_null(long val, char *instr, size_t n, char *str)
{
    str[0] = '\0';
}

/*ARGSUSED*/
static void
at_str(long val, char *instr, size_t n, char *str)
{
    str[0] = '\0';
    if (instr != NULL) {
        (void) strlcpy(str, instr, n);
    }
}

/*
 * Note: Don't forget to add a corresponding case to isainfo(1).
 */

#define FMT_AV(s, n, hwcap, mask, name)             \
    if ((hwcap) & (mask))                   \
        (void) snprintf(s, n, "%s" name " | ", s)

/*ARGSUSED*/
static void
at_hwcap(long val, char *instr, size_t n, char *str)
{
#if defined(__sparc) || defined(__sparcv9)
    (void) elfcap_hw1_to_str(ELFCAP_STYLE_UC, val, str, n,
        ELFCAP_FMT_PIPSPACE, EM_SPARC);

#elif defined(__i386) || defined(__amd64)
    (void) elfcap_hw1_to_str(ELFCAP_STYLE_UC, val, str, n,
        ELFCAP_FMT_PIPSPACE, EM_386);
#else
#error  "port me"
#endif
}

/*ARGSUSED*/
static void
at_hwcap2(long val, char *instr, size_t n, char *str)
{
#if defined(__sparc) || defined(__sparcv9)
    (void) elfcap_hw2_to_str(ELFCAP_STYLE_UC, val, str, n,
        ELFCAP_FMT_PIPSPACE, EM_SPARC);

#elif defined(__i386) || defined(__amd64)
    (void) elfcap_hw2_to_str(ELFCAP_STYLE_UC, val, str, n,
        ELFCAP_FMT_PIPSPACE, EM_386);
#else
#error  "port me"
#endif
}


/*ARGSUSED*/
static void
at_uid(long val, char *instr, size_t n, char *str)
{
    struct passwd *pw = getpwuid((uid_t)val);

    if ((pw == NULL) || (pw->pw_name == NULL))
        str[0] = '\0';
    else
        (void) snprintf(str, n, "%lu(%s)", val, pw->pw_name);
}


/*ARGSUSED*/
static void
at_gid(long val, char *instr, size_t n, char *str)
{
    struct group *gr = getgrgid((gid_t)val);

    if ((gr == NULL) || (gr->gr_name == NULL))
        str[0] = '\0';
    else
        (void) snprintf(str, n, "%lu(%s)", val, gr->gr_name);
}

static struct auxfl {
    int af_flag;
    const char *af_name;
} auxfl[] = {
    { AF_SUN_SETUGID,   "setugid" },
};

/*ARGSUSED*/
static void
at_flags(long val, char *instr, size_t n, char *str)
{
    int i;

    *str = '\0';

    for (i = 0; i < sizeof (auxfl)/sizeof (struct auxfl); i++) {
        if ((val & auxfl[i].af_flag) != 0) {
            if (*str != '\0')
                (void) strlcat(str, ",", n);
            (void) strlcat(str, auxfl[i].af_name, n);
        }
    }
}

#define MAX_AT_NAME_LEN 15

struct aux_id {
    int aux_type;
    const char *aux_name;
    void (*aux_decode)(long, char *, size_t, char *);
};

static struct aux_id aux_arr[] = {
    { AT_NULL,      "AT_NULL",      at_null },
    { AT_IGNORE,        "AT_IGNORE",        at_null },
    { AT_EXECFD,        "AT_EXECFD",        at_null },
    { AT_PHDR,      "AT_PHDR",      at_null },
    { AT_PHENT,     "AT_PHENT",     at_null },
    { AT_PHNUM,     "AT_PHNUM",     at_null },
    { AT_PAGESZ,        "AT_PAGESZ",        at_null },
    { AT_BASE,      "AT_BASE",      at_null },
    { AT_FLAGS,     "AT_FLAGS",     at_null },
    { AT_ENTRY,     "AT_ENTRY",     at_null },
    { AT_SUN_UID,       "AT_SUN_UID",       at_uid  },
    { AT_SUN_RUID,      "AT_SUN_RUID",      at_uid  },
    { AT_SUN_GID,       "AT_SUN_GID",       at_gid  },
    { AT_SUN_RGID,      "AT_SUN_RGID",      at_gid  },
    { AT_SUN_LDELF,     "AT_SUN_LDELF",     at_null },
    { AT_SUN_LDSHDR,    "AT_SUN_LDSHDR",    at_null },
    { AT_SUN_LDNAME,    "AT_SUN_LDNAME",    at_null },
    { AT_SUN_LPAGESZ,   "AT_SUN_LPAGESZ",   at_null },
    { AT_SUN_PLATFORM,  "AT_SUN_PLATFORM",  at_str  },
    { AT_SUN_EXECNAME,  "AT_SUN_EXECNAME",  at_str  },
    { AT_SUN_HWCAP,     "AT_SUN_HWCAP",     at_hwcap },
    { AT_SUN_HWCAP2,    "AT_SUN_HWCAP2",    at_hwcap2 },
    { AT_SUN_IFLUSH,    "AT_SUN_IFLUSH",    at_null },
    { AT_SUN_CPU,       "AT_SUN_CPU",       at_null },
    { AT_SUN_MMU,       "AT_SUN_MMU",       at_null },
    { AT_SUN_LDDATA,    "AT_SUN_LDDATA",    at_null },
    { AT_SUN_AUXFLAGS,  "AT_SUN_AUXFLAGS",  at_flags },
    { AT_SUN_EMULATOR,  "AT_SUN_EMULATOR",  at_str  },
    { AT_SUN_BRANDNAME, "AT_SUN_BRANDNAME", at_str  },
    { AT_SUN_BRAND_AUX1,    "AT_SUN_BRAND_AUX1",    at_null },
    { AT_SUN_BRAND_AUX2,    "AT_SUN_BRAND_AUX2",    at_null },
    { AT_SUN_BRAND_AUX3,    "AT_SUN_BRAND_AUX3",    at_null }
};

#define N_AT_ENTS (sizeof (aux_arr) / sizeof (struct aux_id))

/*
 * Return the aux_id entry for the given aux type; returns NULL if not found.
 */
static struct aux_id *
aux_find(int type)
{
    int i;

    for (i = 0; i < N_AT_ENTS; i++) {
        if (type == aux_arr[i].aux_type)
            return (&aux_arr[i]);
    }

    return (NULL);
}

static void
get_auxv(pargs_data_t *datap)
{
    int i;
    const auxv_t *auxvp;

    /*
     * Fetch the aux vector from the target process.
     */
    if (ps_pauxv(datap->pd_proc, &auxvp) != PS_OK)
        return;

    for (i = 0; auxvp[i].a_type != AT_NULL; i++)
        continue;

    datap->pd_auxc = i;
    datap->pd_auxv = safe_zalloc(i * sizeof (auxv_t));
    bcopy(auxvp, datap->pd_auxv, i * sizeof (auxv_t));

    datap->pd_auxv_strs = safe_zalloc(datap->pd_auxc * sizeof (char *));
    for (i = 0; i < datap->pd_auxc; i++) {
        struct aux_id *aux = aux_find(datap->pd_auxv[i].a_type);

        /*
         * Grab strings for those entries which have a string-decoder.
         */
        if ((aux != NULL) && (aux->aux_decode == at_str)) {
            datap->pd_auxv_strs[i] =
                extract_string(datap, datap->pd_auxv[i].a_un.a_val);
        }
    }
}

/*
 * Prepare to convert characters in the victim's character set into user's
 * character set.
 */
static void
setup_conversions(pargs_data_t *datap, int *diflocale)
{
    char *mylocale = NULL, *mycharset = NULL;
    char *targetlocale = NULL, *targetcharset = NULL;

    mycharset = safe_strdup(nl_langinfo(CODESET));

    mylocale = setlocale(LC_CTYPE, NULL);
    if ((mylocale == NULL) || (strcmp(mylocale, "") == 0))
        mylocale = "C";
    mylocale = safe_strdup(mylocale);

    if (datap->pd_conv_flags & CONV_STRICT_ASCII)
        goto done;

    /*
     * If the target's locale is "C" or "POSIX", go fast.
     */
    if ((strcmp(datap->pd_locale, "C") == 0) ||
        (strcmp(datap->pd_locale, "POSIX") == 0)) {
        datap->pd_conv_flags |= CONV_STRICT_ASCII;
        goto done;
    }

    /*
     * Switch to the victim's locale, and discover its character set.
     */
    if (setlocale(LC_ALL, datap->pd_locale) == NULL) {
        (void) fprintf(stderr,
            "%s: Couldn't determine locale of target process.\n",
            command);
        (void) fprintf(stderr,
            "%s: Some strings may not be displayed properly.\n",
            command);
        goto done;
    }

    /*
     * Get LC_CTYPE part of target's locale, and its codeset.
     */
    targetlocale = safe_strdup(setlocale(LC_CTYPE, NULL));
    targetcharset = safe_strdup(nl_langinfo(CODESET));

    /*
     * Now go fully back to the pargs user's locale.
     */
    (void) setlocale(LC_ALL, "");

    /*
     * It's safe to bail here if the lc_ctype of the locales are the
     * same-- we know that their encodings and characters sets are the same.
     */
    if (strcmp(targetlocale, mylocale) == 0)
        goto done;

    *diflocale = 1;

    /*
     * If the codeset of the victim matches our codeset then iconv need
     * not be involved.
     */
    if (strcmp(mycharset, targetcharset) == 0)
        goto done;

    if ((datap->pd_iconv = iconv_open(mycharset, targetcharset))
        == (iconv_t)-1) {
        /*
         * EINVAL indicates there was no conversion available
         * from victim charset to mycharset
         */
        if (errno != EINVAL) {
            (void) fprintf(stderr,
                "%s: failed to initialize iconv: %s\n",
                command, strerror(errno));
            exit(1);
        }
        datap->pd_conv_flags |= CONV_STRICT_ASCII;
    } else {
        datap->pd_conv_flags |= CONV_USE_ICONV;
    }
done:
    free(mycharset);
    free(mylocale);
    free(targetcharset);
    free(targetlocale);
}

static void
cleanup_conversions(pargs_data_t *datap)
{
    if (datap->pd_conv_flags & CONV_USE_ICONV) {
        (void) iconv_close(datap->pd_iconv);
    }
}

static char *
convert_run_iconv(pargs_data_t *datap, const char *str)
{
    size_t inleft, outleft, bufsz = 64;
    char *outstr, *outstrptr;
    const char *instrptr;

    for (;;) {
        outstrptr = outstr = safe_zalloc(bufsz + 1);
        outleft = bufsz;

        /*
         * Generate the "initial shift state" sequence, placing that
         * at the head of the string.
         */
        inleft = 0;
        (void) iconv(datap->pd_iconv, NULL, &inleft,
            &outstrptr, &outleft);

        inleft = strlen(str);
        instrptr = str;
        if (iconv(datap->pd_iconv, &instrptr, &inleft, &outstrptr,
            &outleft) != (size_t)-1) {
            /*
             * Outstr must be null terminated upon exit from
             * iconv().
             */
            *(outstr + (bufsz - outleft)) = '\0';
            break;
        } else if (errno == E2BIG) {
            bufsz *= 2;
            free(outstr);
        } else if ((errno == EILSEQ) || (errno == EINVAL)) {
            free(outstr);
            return (NULL);
        } else {
            /*
             * iconv() could in theory return EBADF, but that
             * shouldn't happen.
             */
            (void) fprintf(stderr,
                "%s: iconv(3C) failed unexpectedly: %s\n",
                command, strerror(errno));

            exit(1);
        }
    }
    return (outstr);
}

/*
 * Returns a freshly allocated string converted to the local character set,
 * removed of unprintable characters.
 */
static char *
convert_str(pargs_data_t *datap, const char *str, int *unprintable)
{
    char *retstr, *tmp;

    if (datap->pd_conv_flags & CONV_STRICT_ASCII) {
        retstr = unctrl_str_strict_ascii(str, 1, unprintable);
        return (retstr);
    }

    if ((datap->pd_conv_flags & CONV_USE_ICONV) == 0) {
        /*
         * If we aren't using iconv(), convert control chars in
         * the string in pargs' locale, since that is the display
         * locale.
         */
        retstr = unctrl_str(str, 1, unprintable);
        return (retstr);
    }

    /*
     * The logic here is a bit (ahem) tricky.  Start by converting
     * unprintable characters *in the target's locale*.  This should
     * eliminate a variety of unprintable or illegal characters-- in
     * short, it should leave us with something which iconv() won't
     * have trouble with.
     *
     * After allowing iconv to convert characters as needed, run unctrl
     * again in pargs' locale-- This time to make sure that any
     * characters which aren't printable according to the *current*
     * locale (independent of the current codeset) get taken care of.
     * Without this second stage, we might (for example) fail to
     * properly handle characters converted into the 646 character set
     * (which are 8-bits wide), but which must be displayed in the C
     * locale (which uses 646, but whose printable characters are a
     * subset of the 7-bit characters).
     *
     * Note that assuming the victim's locale using LC_ALL will be
     * problematic when pargs' messages are internationalized in the
     * future (and it calls textdomain(3C)).  In this case, any
     * error message fprintf'd in unctrl_str() will be in the wrong
     * LC_MESSAGES class.  We'll cross that bridge when we come to it.
     */
    (void) setlocale(LC_ALL, datap->pd_locale);
    retstr = unctrl_str(str, 1, unprintable);
    (void) setlocale(LC_ALL, "");

    tmp = retstr;
    if ((retstr = convert_run_iconv(datap, retstr)) == NULL) {
        /*
         * In this (rare but real) case, the iconv() failed even
         * though we unctrl'd the string.  Treat the original string
         * (str) as a C locale string and strip it that way.
         */
        free(tmp);
        return (unctrl_str_strict_ascii(str, 0, unprintable));
    }

    free(tmp);
    tmp = retstr;
    /*
     * Run unctrl_str, but make sure not to escape \ characters, which
     * may have resulted from the first round of unctrl.
     */
    retstr = unctrl_str(retstr, 0, unprintable);
    free(tmp);
    return (retstr);
}


static void
convert_array(pargs_data_t *datap, char **arr, size_t count, int *unprintable)
{
    int i;
    char *tmp;

    if (arr == NULL)
        return;

    for (i = 0; i < count; i++) {
        if ((tmp = arr[i]) == NULL)
            continue;
        arr[i] = convert_str(datap, arr[i], unprintable);
        free(tmp);
    }
}

/*
 * Free data allocated during the gathering phase.
 */
static void
free_data(pargs_data_t *datap)
{
    int i;

    if (datap->pd_argv) {
        for (i = 0; i < datap->pd_argc; i++) {
            if (datap->pd_argv_strs[i] != NULL)
                free(datap->pd_argv_strs[i]);
        }
        free(datap->pd_argv);
        free(datap->pd_argv_strs);
    }

    if (datap->pd_envp) {
        for (i = 0; i < datap->pd_envc; i++) {
            if (datap->pd_envp_strs[i] != NULL)
                free(datap->pd_envp_strs[i]);
        }
        free(datap->pd_envp);
        free(datap->pd_envp_strs);
    }

    if (datap->pd_auxv) {
        for (i = 0; i < datap->pd_auxc; i++) {
            if (datap->pd_auxv_strs[i] != NULL)
                free(datap->pd_auxv_strs[i]);
        }
        free(datap->pd_auxv);
        free(datap->pd_auxv_strs);
    }
}

static void
print_args(pargs_data_t *datap)
{
    int i;

    if (datap->pd_argv == NULL) {
        (void) fprintf(stderr, "%s: failed to read argv[]\n", command);
        return;
    }

    for (i = 0; i < datap->pd_argc; i++) {
        (void) printf("argv[%d]: ", i);
        if (datap->pd_argv[i] == NULL) {
            (void) printf("<NULL>\n");
        } else if (datap->pd_argv_strs[i] == NULL) {
            (void) printf("<0x%0*lx>\n",
                (dmodel == PR_MODEL_LP64)? 16 : 8,
                (long)datap->pd_argv[i]);
        } else {
            (void) printf("%s\n", datap->pd_argv_strs[i]);
        }
    }
}

static void
print_env(pargs_data_t *datap)
{
    int i;

    if (datap->pd_envp == NULL) {
        (void) fprintf(stderr, "%s: failed to read envp[]\n", command);
        return;
    }

    for (i = 0; i < datap->pd_envc; i++) {
        (void) printf("envp[%d]: ", i);
        if (datap->pd_envp[i] == 0) {
            break;
        } else if (datap->pd_envp_strs[i] == NULL) {
            (void) printf("<0x%0*lx>\n",
                (dmodel == PR_MODEL_LP64)? 16 : 8,
                (long)datap->pd_envp[i]);
        } else {
            (void) printf("%s\n", datap->pd_envp_strs[i]);
        }
    }
}

static int
print_cmdline(pargs_data_t *datap)
{
    int i;

    /*
     * Go through and check to see if we have valid data.  If not, print
     * an error message and bail.
     */
    for (i = 0; i < datap->pd_argc; i++) {
        if (datap->pd_argv == NULL || datap->pd_argv[i] == NULL ||
            datap->pd_argv_strs[i] == NULL) {
            (void) fprintf(stderr, "%s: target has corrupted "
                "argument list\n", command);
            return (1);
        }

        datap->pd_argv_strs[i] =
            quote_string(datap, datap->pd_argv_strs[i]);
    }

    if (datap->pd_execname == NULL) {
        (void) fprintf(stderr, "%s: cannot determine name of "
            "executable\n", command);
        return (1);
    }

    (void) printf("%s ", datap->pd_execname);

    for (i = 1; i < datap->pd_argc; i++)
        (void) printf("%s ", datap->pd_argv_strs[i]);

    (void) printf("\n");

    return (0);
}

static void
print_auxv(pargs_data_t *datap)
{
    int i;
    const auxv_t *pa;

    /*
     * Print the names and values of all the aux vector entries.
     */
    for (i = 0; i < datap->pd_auxc; i++) {
        char type[32];
        char decode[PATH_MAX];
        struct aux_id *aux;
        long v;
        pa = &datap->pd_auxv[i];

        aux = aux_find(pa->a_type);
        v = (long)pa->a_un.a_val;

        if (aux != NULL) {
            /*
             * Fetch aux vector type string and decoded
             * representation of the value.
             */
            (void) strlcpy(type, aux->aux_name, sizeof (type));
            aux->aux_decode(v, datap->pd_auxv_strs[i],
                sizeof (decode), decode);
        } else {
            (void) snprintf(type, sizeof (type), "%d", pa->a_type);
            decode[0] = '\0';
        }

        (void) printf("%-*s 0x%0*lx %s\n", MAX_AT_NAME_LEN, type,
            (dmodel == PR_MODEL_LP64)? 16 : 8, v, decode);
    }
}

int
main(int argc, char *argv[])
{
    int aflag = 0, cflag = 0, eflag = 0, xflag = 0, lflag = 0;
    int errflg = 0, retc = 0;
    int opt;
    int error = 1;
    core_content_t content = 0;

    (void) setlocale(LC_ALL, "");

    if ((command = strrchr(argv[0], '/')) != NULL)
        command++;
    else
        command = argv[0];

    while ((opt = getopt(argc, argv, "acelxF")) != EOF) {
        switch (opt) {
        case 'a':       /* show process arguments */
            content |= CC_CONTENT_STACK;
            aflag++;
            break;
        case 'c':       /* force 7-bit ascii */
            cflag++;
            break;
        case 'e':       /* show environment variables */
            content |= CC_CONTENT_STACK;
            eflag++;
            break;
        case 'l':
            lflag++;
            aflag++;    /* -l implies -a */
            break;
        case 'x':       /* show aux vector entries */
            xflag++;
            break;
        case 'F':
            /*
             * Since we open the process read-only, there is no need
             * for the -F flag.  It's a documented flag, so we
             * consume it silently.
             */
            break;
        default:
            errflg++;
            break;
        }
    }

    /* -a is the default if no options are specified */
    if ((aflag + eflag + xflag + lflag) == 0) {
        aflag++;
        content |= CC_CONTENT_STACK;
    }

    /* -l cannot be used with the -x or -e flags */
    if (lflag && (xflag || eflag)) {
        (void) fprintf(stderr, "-l is incompatible with -x and -e\n");
        errflg++;
    }

    argc -= optind;
    argv += optind;

    if (errflg || argc <= 0) {
        (void) fprintf(stderr,
            "usage:  %s [-aceFlx] { pid | core } ...\n"
            "  (show process arguments and environment)\n"
            "  -a: show process arguments (default)\n"
            "  -c: interpret characters as 7-bit ascii regardless of "
            "locale\n"
            "  -e: show environment variables\n"
            "  -F: force grabbing of the target process\n"
            "  -l: display arguments as command line\n"
            "  -x: show aux vector entries\n", command);
        return (2);
    }

    while (argc-- > 0) {
        char *arg;
        int gret, r;
        psinfo_t psinfo;
        char *psargs_conv;
        struct ps_prochandle *Pr;
        pargs_data_t datap;
        char *info;
        size_t info_sz;
        int pstate;
        char execname[PATH_MAX];
        int unprintable;
        int diflocale;

        (void) fflush(stdout);
        arg = *argv++;

        /*
         * Suppress extra blanks lines if we've encountered processes
         * which can't be opened.
         */
        if (error == 0) {
            (void) printf("\n");
        }
        error = 0;

        /*
         * First grab just the psinfo information, in case this
         * process is a zombie (in which case proc_arg_grab() will
         * fail).  If so, print a nice message and continue.
         */
        if (proc_arg_psinfo(arg, PR_ARG_ANY, &psinfo,
            &gret) == -1) {
            (void) fprintf(stderr, "%s: cannot examine %s: %s\n",
                command, arg, Pgrab_error(gret));
            retc++;
            error = 1;
            continue;
        }

        if (psinfo.pr_nlwp == 0) {
            (void) printf("%d: <defunct>\n", (int)psinfo.pr_pid);
            continue;
        }

        /*
         * If process is a "system" process (like pageout), just
         * print its psargs and continue on.
         */
        if (psinfo.pr_size == 0 && psinfo.pr_rssize == 0) {
            proc_unctrl_psinfo(&psinfo);
            if (!lflag)
                (void) printf("%d: ", (int)psinfo.pr_pid);
            (void) printf("%s\n", psinfo.pr_psargs);
            continue;
        }

        /*
         * Open the process readonly, since we do not need to write to
         * the control file.
         */
        if ((Pr = proc_arg_grab(arg, PR_ARG_ANY, PGRAB_RDONLY,
            &gret)) == NULL) {
            (void) fprintf(stderr, "%s: cannot examine %s: %s\n",
                command, arg, Pgrab_error(gret));
            retc++;
            error = 1;
            continue;
        }

        pstate = Pstate(Pr);

        if (pstate == PS_DEAD &&
            (Pcontent(Pr) & content) != content) {
            (void) fprintf(stderr, "%s: core '%s' has "
                "insufficient content\n", command, arg);
            retc++;
            continue;
        }

        /*
         * If malloc() fails, we return here so that we can let go
         * of the victim, restore our locale, print a message,
         * then exit.
         */
        if ((r = setjmp(env)) != 0) {
            Prelease(Pr, 0);
            (void) setlocale(LC_ALL, "");
            (void) fprintf(stderr, "%s: out of memory: %s\n",
                command, strerror(r));
            return (1);
        }

        dmodel = Pstatus(Pr)->pr_dmodel;
        bzero(&datap, sizeof (datap));
        bcopy(Ppsinfo(Pr), &psinfo, sizeof (psinfo_t));
        datap.pd_proc = Pr;
        datap.pd_psinfo = &psinfo;

        if (cflag)
            datap.pd_conv_flags |= CONV_STRICT_ASCII;

        /*
         * Strip control characters, then record process summary in
         * a buffer, since we don't want to print anything out until
         * after we release the process.
         */

        /*
         * The process is neither a system process nor defunct.
         *
         * Do printing and post-processing (like name lookups) after
         * gathering the raw data from the process and releasing it.
         * This way, we don't deadlock on (for example) name lookup
         * if we grabbed the nscd and do 'pargs -x'.
         *
         * We always fetch the environment of the target, so that we
         * can make an educated guess about its locale.
         */
        get_env(&datap);
        if (aflag != 0)
            get_args(&datap);
        if (xflag != 0)
            get_auxv(&datap);

        /*
         * If malloc() fails after this poiint, we return here to
         * restore our locale and print a message.  If we don't
         * reset this, we might erroneously try to Prelease a process
         * twice.
         */
        if ((r = setjmp(env)) != 0) {
            (void) setlocale(LC_ALL, "");
            (void) fprintf(stderr, "%s: out of memory: %s\n",
                command, strerror(r));
            return (1);
        }

        /*
         * For the -l option, we need a proper name for this executable
         * before we release it.
         */
        if (lflag)
            datap.pd_execname = Pexecname(Pr, execname,
                sizeof (execname));

        Prelease(Pr, 0);

        /*
         * Crawl through the environment to determine the locale of
         * the target.
         */
        lookup_locale(&datap);
        diflocale = 0;
        setup_conversions(&datap, &diflocale);

        if (lflag != 0) {
            unprintable = 0;
            convert_array(&datap, datap.pd_argv_strs,
                datap.pd_argc, &unprintable);
            if (diflocale)
                (void) fprintf(stderr, "%s: Warning, target "
                    "locale differs from current locale\n",
                    command);
            else if (unprintable)
                (void) fprintf(stderr, "%s: Warning, command "
                    "line contains unprintable characters\n",
                    command);

            retc += print_cmdline(&datap);
        } else {
            psargs_conv = convert_str(&datap, psinfo.pr_psargs,
                &unprintable);
            info_sz = strlen(psargs_conv) + MAXPATHLEN + 32 + 1;
            info = malloc(info_sz);
            if (pstate == PS_DEAD) {
                (void) snprintf(info, info_sz,
                    "core '%s' of %d:\t%s\n",
                    arg, (int)psinfo.pr_pid, psargs_conv);
            } else {
                (void) snprintf(info, info_sz, "%d:\t%s\n",
                    (int)psinfo.pr_pid, psargs_conv);
            }
            (void) printf("%s", info);
            free(info);
            free(psargs_conv);

            if (aflag != 0) {
                convert_array(&datap, datap.pd_argv_strs,
                    datap.pd_argc, &unprintable);
                print_args(&datap);
                if (eflag || xflag)
                    (void) printf("\n");
            }

            if (eflag != 0) {
                convert_array(&datap, datap.pd_envp_strs,
                    datap.pd_envc, &unprintable);
                print_env(&datap);
                if (xflag)
                    (void) printf("\n");
            }

            if (xflag != 0) {
                convert_array(&datap, datap.pd_auxv_strs,
                    datap.pd_auxc, &unprintable);
                print_auxv(&datap);
            }
        }

        cleanup_conversions(&datap);
        free_data(&datap);
    }

    return (retc != 0 ? 1 : 0);
}