Adding upstream version 3.6.upstream/3.6upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1080 insertions, 0 deletions

diff --git a/lib/quotearg.c b/lib/quotearg.c
new file mode 100644
index 0000000..975bd61
--- /dev/null
+++ b/lib/quotearg.c
@@ -0,0 +1,1080 @@
+/* quotearg.c - quote arguments for output
+
+   Copyright (C) 1998-2002, 2004-2023 Free Software Foundation, Inc.
+
+   This program is free software: you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation, either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
+
+/* Written by Paul Eggert <eggert@twinsun.com> */
+
+/* Without this pragma, gcc 4.7.0 20111124 mistakenly suggests that
+   the quoting_options_from_style function might be candidate for
+   attribute 'pure'  */
+#if (__GNUC__ == 4 && 6 <= __GNUC_MINOR__) || 4 < __GNUC__
+# pragma GCC diagnostic ignored "-Wsuggest-attribute=pure"
+#endif
+
+#include <config.h>
+
+#include "quotearg.h"
+#include "quote.h"
+
+#include "attribute.h"
+#include "minmax.h"
+#include "xalloc.h"
+#include "c-strcaseeq.h"
+#include "localcharset.h"
+
+#include <ctype.h>
+#include <errno.h>
+#include <limits.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <string.h>
+#include <wchar.h>
+#include <wctype.h>
+
+#include "gettext.h"
+#define _(msgid) gettext (msgid)
+#define N_(msgid) msgid
+
+#ifndef SIZE_MAX
+# define SIZE_MAX ((size_t) -1)
+#endif
+
+#define INT_BITS (sizeof (int) * CHAR_BIT)
+
+struct quoting_options
+{
+  /* Basic quoting style.  */
+  enum quoting_style style;
+
+  /* Additional flags.  Bitwise combination of enum quoting_flags.  */
+  int flags;
+
+  /* Quote the characters indicated by this bit vector even if the
+     quoting style would not normally require them to be quoted.  */
+  unsigned int quote_these_too[(UCHAR_MAX / INT_BITS) + 1];
+
+  /* The left quote for custom_quoting_style.  */
+  char const *left_quote;
+
+  /* The right quote for custom_quoting_style.  */
+  char const *right_quote;
+};
+
+/* Names of quoting styles.  */
+char const *const quoting_style_args[] =
+{
+  "literal",
+  "shell",
+  "shell-always",
+  "shell-escape",
+  "shell-escape-always",
+  "c",
+  "c-maybe",
+  "escape",
+  "locale",
+  "clocale",
+  0
+};
+
+/* Correspondences to quoting style names.  */
+enum quoting_style const quoting_style_vals[] =
+{
+  literal_quoting_style,
+  shell_quoting_style,
+  shell_always_quoting_style,
+  shell_escape_quoting_style,
+  shell_escape_always_quoting_style,
+  c_quoting_style,
+  c_maybe_quoting_style,
+  escape_quoting_style,
+  locale_quoting_style,
+  clocale_quoting_style
+};
+
+/* The default quoting options.  */
+static struct quoting_options default_quoting_options;
+
+/* Allocate a new set of quoting options, with contents initially identical
+   to O if O is not null, or to the default if O is null.
+   It is the caller's responsibility to free the result.  */
+struct quoting_options *
+clone_quoting_options (struct quoting_options *o)
+{
+  int e = errno;
+  struct quoting_options *p = xmemdup (o ? o : &default_quoting_options,
+                                       sizeof *o);
+  errno = e;
+  return p;
+}
+
+/* Get the value of O's quoting style.  If O is null, use the default.  */
+enum quoting_style
+get_quoting_style (struct quoting_options const *o)
+{
+  return (o ? o : &default_quoting_options)->style;
+}
+
+/* In O (or in the default if O is null),
+   set the value of the quoting style to S.  */
+void
+set_quoting_style (struct quoting_options *o, enum quoting_style s)
+{
+  (o ? o : &default_quoting_options)->style = s;
+}
+
+/* In O (or in the default if O is null),
+   set the value of the quoting options for character C to I.
+   Return the old value.  Currently, the only values defined for I are
+   0 (the default) and 1 (which means to quote the character even if
+   it would not otherwise be quoted).  */
+int
+set_char_quoting (struct quoting_options *o, char c, int i)
+{
+  unsigned char uc = c;
+  unsigned int *p =
+    (o ? o : &default_quoting_options)->quote_these_too + uc / INT_BITS;
+  int shift = uc % INT_BITS;
+  int r = (*p >> shift) & 1;
+  *p ^= ((i & 1) ^ r) << shift;
+  return r;
+}
+
+/* In O (or in the default if O is null),
+   set the value of the quoting options flag to I, which can be a
+   bitwise combination of enum quoting_flags, or 0 for default
+   behavior.  Return the old value.  */
+int
+set_quoting_flags (struct quoting_options *o, int i)
+{
+  int r;
+  if (!o)
+    o = &default_quoting_options;
+  r = o->flags;
+  o->flags = i;
+  return r;
+}
+
+void
+set_custom_quoting (struct quoting_options *o,
+                    char const *left_quote, char const *right_quote)
+{
+  if (!o)
+    o = &default_quoting_options;
+  o->style = custom_quoting_style;
+  if (!left_quote || !right_quote)
+    abort ();
+  o->left_quote = left_quote;
+  o->right_quote = right_quote;
+}
+
+/* Return quoting options for STYLE, with no extra quoting.  */
+static struct quoting_options /* NOT PURE!! */
+quoting_options_from_style (enum quoting_style style)
+{
+  struct quoting_options o = { literal_quoting_style, 0, { 0 }, NULL, NULL };
+  if (style == custom_quoting_style)
+    abort ();
+  o.style = style;
+  return o;
+}
+
+/* MSGID approximates a quotation mark.  Return its translation if it
+   has one; otherwise, return either it or "\"", depending on S.
+
+   S is either clocale_quoting_style or locale_quoting_style.  */
+static char const *
+gettext_quote (char const *msgid, enum quoting_style s)
+{
+  char const *translation = _(msgid);
+  char const *locale_code;
+
+  if (translation != msgid)
+    return translation;
+
+  /* For UTF-8 and GB-18030, use single quotes U+2018 and U+2019.
+     Here is a list of other locales that include U+2018 and U+2019:
+
+        ISO-8859-7   0xA1                 KOI8-T       0x91
+        CP869        0x8B                 CP874        0x91
+        CP932        0x81 0x65            CP936        0xA1 0xAE
+        CP949        0xA1 0xAE            CP950        0xA1 0xA5
+        CP1250       0x91                 CP1251       0x91
+        CP1252       0x91                 CP1253       0x91
+        CP1254       0x91                 CP1255       0x91
+        CP1256       0x91                 CP1257       0x91
+        EUC-JP       0xA1 0xC6            EUC-KR       0xA1 0xAE
+        EUC-TW       0xA1 0xE4            BIG5         0xA1 0xA5
+        BIG5-HKSCS   0xA1 0xA5            EUC-CN       0xA1 0xAE
+        GBK          0xA1 0xAE            Georgian-PS  0x91
+        PT154        0x91
+
+     None of these is still in wide use; using iconv is overkill.  */
+  locale_code = locale_charset ();
+  if (STRCASEEQ (locale_code, "UTF-8", 'U','T','F','-','8',0,0,0,0))
+    return msgid[0] == '`' ? "\xe2\x80\x98": "\xe2\x80\x99";
+  if (STRCASEEQ (locale_code, "GB18030", 'G','B','1','8','0','3','0',0,0))
+    return msgid[0] == '`' ? "\xa1\ae": "\xa1\xaf";
+
+  return (s == clocale_quoting_style ? "\"" : "'");
+}
+
+/* Place into buffer BUFFER (of size BUFFERSIZE) a quoted version of
+   argument ARG (of size ARGSIZE), using QUOTING_STYLE, FLAGS, and
+   QUOTE_THESE_TOO to control quoting.
+   Terminate the output with a null character, and return the written
+   size of the output, not counting the terminating null.
+   If BUFFERSIZE is too small to store the output string, return the
+   value that would have been returned had BUFFERSIZE been large enough.
+   If ARGSIZE is SIZE_MAX, use the string length of the argument for ARGSIZE.
+
+   This function acts like quotearg_buffer (BUFFER, BUFFERSIZE, ARG,
+   ARGSIZE, O), except it breaks O into its component pieces and is
+   not careful about errno.  */
+
+static size_t
+quotearg_buffer_restyled (char *buffer, size_t buffersize,
+                          char const *arg, size_t argsize,
+                          enum quoting_style quoting_style, int flags,
+                          unsigned int const *quote_these_too,
+                          char const *left_quote,
+                          char const *right_quote)
+{
+  size_t i;
+  size_t len = 0;
+  size_t orig_buffersize = 0;
+  char const *quote_string = 0;
+  size_t quote_string_len = 0;
+  bool backslash_escapes = false;
+  bool unibyte_locale = MB_CUR_MAX == 1;
+  bool elide_outer_quotes = (flags & QA_ELIDE_OUTER_QUOTES) != 0;
+  bool pending_shell_escape_end = false;
+  bool encountered_single_quote = false;
+  bool all_c_and_shell_quote_compat = true;
+
+#define STORE(c) \
+    do \
+      { \
+        if (len < buffersize) \
+          buffer[len] = (c); \
+        len++; \
+      } \
+    while (0)
+
+#define START_ESC() \
+    do \
+      { \
+        if (elide_outer_quotes) \
+          goto force_outer_quoting_style; \
+        escaping = true; \
+        if (quoting_style == shell_always_quoting_style \
+            && ! pending_shell_escape_end) \
+          { \
+            STORE ('\''); \
+            STORE ('$'); \
+            STORE ('\''); \
+            pending_shell_escape_end = true; \
+          } \
+        STORE ('\\'); \
+      } \
+    while (0)
+
+#define END_ESC() \
+    do \
+      { \
+        if (pending_shell_escape_end && ! escaping) \
+          { \
+            STORE ('\''); \
+            STORE ('\''); \
+            pending_shell_escape_end = false; \
+          } \
+      } \
+    while (0)
+
+ process_input:
+
+  switch (quoting_style)
+    {
+    case c_maybe_quoting_style:
+      quoting_style = c_quoting_style;
+      elide_outer_quotes = true;
+      FALLTHROUGH;
+    case c_quoting_style:
+      if (!elide_outer_quotes)
+        STORE ('"');
+      backslash_escapes = true;
+      quote_string = "\"";
+      quote_string_len = 1;
+      break;
+
+    case escape_quoting_style:
+      backslash_escapes = true;
+      elide_outer_quotes = false;
+      break;
+
+    case locale_quoting_style:
+    case clocale_quoting_style:
+    case custom_quoting_style:
+      {
+        if (quoting_style != custom_quoting_style)
+          {
+            /* TRANSLATORS:
+               Get translations for open and closing quotation marks.
+               The message catalog should translate "`" to a left
+               quotation mark suitable for the locale, and similarly for
+               "'".  For example, a French Unicode local should translate
+               these to U+00AB (LEFT-POINTING DOUBLE ANGLE
+               QUOTATION MARK), and U+00BB (RIGHT-POINTING DOUBLE ANGLE
+               QUOTATION MARK), respectively.
+
+               If the catalog has no translation, we will try to
+               use Unicode U+2018 (LEFT SINGLE QUOTATION MARK) and
+               Unicode U+2019 (RIGHT SINGLE QUOTATION MARK).  If the
+               current locale is not Unicode, locale_quoting_style
+               will quote 'like this', and clocale_quoting_style will
+               quote "like this".  You should always include translations
+               for "`" and "'" even if U+2018 and U+2019 are appropriate
+               for your locale.
+
+               If you don't know what to put here, please see
+               <https://en.wikipedia.org/wiki/Quotation_marks_in_other_languages>
+               and use glyphs suitable for your language.  */
+            left_quote = gettext_quote (N_("`"), quoting_style);
+            right_quote = gettext_quote (N_("'"), quoting_style);
+          }
+        if (!elide_outer_quotes)
+          for (quote_string = left_quote; *quote_string; quote_string++)
+            STORE (*quote_string);
+        backslash_escapes = true;
+        quote_string = right_quote;
+        quote_string_len = strlen (quote_string);
+      }
+      break;
+
+    case shell_escape_quoting_style:
+      backslash_escapes = true;
+      FALLTHROUGH;
+    case shell_quoting_style:
+      elide_outer_quotes = true;
+      FALLTHROUGH;
+    case shell_escape_always_quoting_style:
+      if (!elide_outer_quotes)
+        backslash_escapes = true;
+      FALLTHROUGH;
+    case shell_always_quoting_style:
+      quoting_style = shell_always_quoting_style;
+      if (!elide_outer_quotes)
+        STORE ('\'');
+      quote_string = "'";
+      quote_string_len = 1;
+      break;
+
+    case literal_quoting_style:
+      elide_outer_quotes = false;
+      break;
+
+    default:
+      abort ();
+    }
+
+  for (i = 0;  ! (argsize == SIZE_MAX ? arg[i] == '\0' : i == argsize);  i++)
+    {
+      unsigned char c;
+      unsigned char esc;
+      bool is_right_quote = false;
+      bool escaping = false;
+      bool c_and_shell_quote_compat = false;
+
+      if (backslash_escapes
+          && quoting_style != shell_always_quoting_style
+          && quote_string_len
+          && (i + quote_string_len
+              <= (argsize == SIZE_MAX && 1 < quote_string_len
+                  /* Use strlen only if we must: when argsize is SIZE_MAX,
+                     and when the quote string is more than 1 byte long.
+                     If we do call strlen, save the result.  */
+                  ? (argsize = strlen (arg)) : argsize))
+          && memcmp (arg + i, quote_string, quote_string_len) == 0)
+        {
+          if (elide_outer_quotes)
+            goto force_outer_quoting_style;
+          is_right_quote = true;
+        }
+
+      c = arg[i];
+      switch (c)
+        {
+        case '\0':
+          if (backslash_escapes)
+            {
+              START_ESC ();
+              /* If quote_string were to begin with digits, we'd need to
+                 test for the end of the arg as well.  However, it's
+                 hard to imagine any locale that would use digits in
+                 quotes, and set_custom_quoting is documented not to
+                 accept them.  Use only a single \0 with shell-escape
+                 as currently digits are not printed within $'...'  */
+              if (quoting_style != shell_always_quoting_style
+                  && i + 1 < argsize && '0' <= arg[i + 1] && arg[i + 1] <= '9')
+                {
+                  STORE ('0');
+                  STORE ('0');
+                }
+              c = '0';
+              /* We don't have to worry that this last '0' will be
+                 backslash-escaped because, again, quote_string should
+                 not start with it and because quote_these_too is
+                 documented as not accepting it.  */
+            }
+          else if (flags & QA_ELIDE_NULL_BYTES)
+            continue;
+          break;
+
+        case '?':
+          switch (quoting_style)
+            {
+            case shell_always_quoting_style:
+              if (elide_outer_quotes)
+                goto force_outer_quoting_style;
+              break;
+
+            case c_quoting_style:
+              if ((flags & QA_SPLIT_TRIGRAPHS)
+                  && i + 2 < argsize && arg[i + 1] == '?')
+                switch (arg[i + 2])
+                  {
+                  case '!': case '\'':
+                  case '(': case ')': case '-': case '/':
+                  case '<': case '=': case '>':
+                    /* Escape the second '?' in what would otherwise be
+                       a trigraph.  */
+                    if (elide_outer_quotes)
+                      goto force_outer_quoting_style;
+                    c = arg[i + 2];
+                    i += 2;
+                    STORE ('?');
+                    STORE ('"');
+                    STORE ('"');
+                    STORE ('?');
+                    break;
+
+                  default:
+                    break;
+                  }
+              break;
+
+            default:
+              break;
+            }
+          break;
+
+        case '\a': esc = 'a'; goto c_escape;
+        case '\b': esc = 'b'; goto c_escape;
+        case '\f': esc = 'f'; goto c_escape;
+        case '\n': esc = 'n'; goto c_and_shell_escape;
+        case '\r': esc = 'r'; goto c_and_shell_escape;
+        case '\t': esc = 't'; goto c_and_shell_escape;
+        case '\v': esc = 'v'; goto c_escape;
+        case '\\': esc = c;
+          /* Never need to escape '\' in shell case.  */
+          if (quoting_style == shell_always_quoting_style)
+            {
+              if (elide_outer_quotes)
+                goto force_outer_quoting_style;
+              goto store_c;
+            }
+
+          /* No need to escape the escape if we are trying to elide
+             outer quotes and nothing else is problematic.  */
+          if (backslash_escapes && elide_outer_quotes && quote_string_len)
+            goto store_c;
+
+        c_and_shell_escape:
+          if (quoting_style == shell_always_quoting_style
+              && elide_outer_quotes)
+            goto force_outer_quoting_style;
+          /* fall through */
+        c_escape:
+          if (backslash_escapes)
+            {
+              c = esc;
+              goto store_escape;
+            }
+          break;
+
+        case '{': case '}': /* sometimes special if isolated */
+          if (! (argsize == SIZE_MAX ? arg[1] == '\0' : argsize == 1))
+            break;
+          FALLTHROUGH;
+        case '#': case '~':
+          if (i != 0)
+            break;
+          FALLTHROUGH;
+        case ' ':
+          c_and_shell_quote_compat = true;
+          FALLTHROUGH;
+        case '!': /* special in bash */
+        case '"': case '$': case '&':
+        case '(': case ')': case '*': case ';':
+        case '<':
+        case '=': /* sometimes special in 0th or (with "set -k") later args */
+        case '>': case '[':
+        case '^': /* special in old /bin/sh, e.g. SunOS 4.1.4 */
+        case '`': case '|':
+          /* A shell special character.  In theory, '$' and '`' could
+             be the first bytes of multibyte characters, which means
+             we should check them with mbrtowc, but in practice this
+             doesn't happen so it's not worth worrying about.  */
+          if (quoting_style == shell_always_quoting_style
+              && elide_outer_quotes)
+            goto force_outer_quoting_style;
+          break;
+
+        case '\'':
+          encountered_single_quote = true;
+          c_and_shell_quote_compat = true;
+          if (quoting_style == shell_always_quoting_style)
+            {
+              if (elide_outer_quotes)
+                goto force_outer_quoting_style;
+
+              if (buffersize && ! orig_buffersize)
+                {
+                  /* Just scan string to see if supports a more concise
+                     representation, rather than writing a longer string
+                     but returning the length of the more concise form.  */
+                  orig_buffersize = buffersize;
+                  buffersize = 0;
+                }
+
+              STORE ('\'');
+              STORE ('\\');
+              STORE ('\'');
+              pending_shell_escape_end = false;
+            }
+          break;
+
+        case '%': case '+': case ',': case '-': case '.': case '/':
+        case '0': case '1': case '2': case '3': case '4': case '5':
+        case '6': case '7': case '8': case '9': case ':':
+        case 'A': case 'B': case 'C': case 'D': case 'E': case 'F':
+        case 'G': case 'H': case 'I': case 'J': case 'K': case 'L':
+        case 'M': case 'N': case 'O': case 'P': case 'Q': case 'R':
+        case 'S': case 'T': case 'U': case 'V': case 'W': case 'X':
+        case 'Y': case 'Z': case ']': case '_': case 'a': case 'b':
+        case 'c': case 'd': case 'e': case 'f': case 'g': case 'h':
+        case 'i': case 'j': case 'k': case 'l': case 'm': case 'n':
+        case 'o': case 'p': case 'q': case 'r': case 's': case 't':
+        case 'u': case 'v': case 'w': case 'x': case 'y': case 'z':
+          /* These characters don't cause problems, no matter what the
+             quoting style is.  They cannot start multibyte sequences.
+             A digit or a special letter would cause trouble if it
+             appeared at the beginning of quote_string because we'd then
+             escape by prepending a backslash.  However, it's hard to
+             imagine any locale that would use digits or letters as
+             quotes, and set_custom_quoting is documented not to accept
+             them.  Also, a digit or a special letter would cause
+             trouble if it appeared in quote_these_too, but that's also
+             documented as not accepting them.  */
+          c_and_shell_quote_compat = true;
+          break;
+
+        default:
+          /* If we have a multibyte sequence, copy it until we reach
+             its end, find an error, or come back to the initial shift
+             state.  For C-like styles, if the sequence has
+             unprintable characters, escape the whole sequence, since
+             we can't easily escape single characters within it.  */
+          {
+            /* Length of multibyte sequence found so far.  */
+            size_t m;
+
+            bool printable;
+
+            if (unibyte_locale)
+              {
+                m = 1;
+                printable = isprint (c) != 0;
+              }
+            else
+              {
+                mbstate_t mbstate;
+                memset (&mbstate, 0, sizeof mbstate);
+
+                m = 0;
+                printable = true;
+                if (argsize == SIZE_MAX)
+                  argsize = strlen (arg);
+
+                do
+                  {
+                    wchar_t w;
+                    size_t bytes = mbrtowc (&w, &arg[i + m],
+                                            argsize - (i + m), &mbstate);
+                    if (bytes == 0)
+                      break;
+                    else if (bytes == (size_t) -1)
+                      {
+                        printable = false;
+                        break;
+                      }
+                    else if (bytes == (size_t) -2)
+                      {
+                        printable = false;
+                        while (i + m < argsize && arg[i + m])
+                          m++;
+                        break;
+                      }
+                    else
+                      {
+                        /* Work around a bug with older shells that "see" a '\'
+                           that is really the 2nd byte of a multibyte character.
+                           In practice the problem is limited to ASCII
+                           chars >= '@' that are shell special chars.  */
+                        if ('[' == 0x5b && elide_outer_quotes
+                            && quoting_style == shell_always_quoting_style)
+                          {
+                            size_t j;
+                            for (j = 1; j < bytes; j++)
+                              switch (arg[i + m + j])
+                                {
+                                case '[': case '\\': case '^':
+                                case '`': case '|':
+                                  goto force_outer_quoting_style;
+
+                                default:
+                                  break;
+                                }
+                          }
+
+                        if (! iswprint (w))
+                          printable = false;
+                        m += bytes;
+                      }
+                  }
+                while (! mbsinit (&mbstate));
+              }
+
+            c_and_shell_quote_compat = printable;
+
+            if (1 < m || (backslash_escapes && ! printable))
+              {
+                /* Output a multibyte sequence, or an escaped
+                   unprintable unibyte character.  */
+                size_t ilim = i + m;
+
+                for (;;)
+                  {
+                    if (backslash_escapes && ! printable)
+                      {
+                        START_ESC ();
+                        STORE ('0' + (c >> 6));
+                        STORE ('0' + ((c >> 3) & 7));
+                        c = '0' + (c & 7);
+                      }
+                    else if (is_right_quote)
+                      {
+                        STORE ('\\');
+                        is_right_quote = false;
+                      }
+                    if (ilim <= i + 1)
+                      break;
+                    END_ESC ();
+                    STORE (c);
+                    c = arg[++i];
+                  }
+
+                goto store_c;
+              }
+          }
+        }
+
+      if (! (((backslash_escapes && quoting_style != shell_always_quoting_style)
+              || elide_outer_quotes)
+             && quote_these_too
+             && quote_these_too[c / INT_BITS] >> (c % INT_BITS) & 1)
+          && !is_right_quote)
+        goto store_c;
+
+    store_escape:
+      START_ESC ();
+
+    store_c:
+      END_ESC ();
+      STORE (c);
+
+      if (! c_and_shell_quote_compat)
+        all_c_and_shell_quote_compat = false;
+    }
+
+  if (len == 0 && quoting_style == shell_always_quoting_style
+      && elide_outer_quotes)
+    goto force_outer_quoting_style;
+
+  /* Single shell quotes (') are commonly enough used as an apostrophe,
+     that we attempt to minimize the quoting in this case.  Note itʼs
+     better to use the apostrophe modifier "\u02BC" if possible, as that
+     renders better and works with the word match regex \W+ etc.  */
+  if (quoting_style == shell_always_quoting_style && ! elide_outer_quotes
+      && encountered_single_quote)
+    {
+      if (all_c_and_shell_quote_compat)
+        return quotearg_buffer_restyled (buffer, orig_buffersize, arg, argsize,
+                                         c_quoting_style,
+                                         flags, quote_these_too,
+                                         left_quote, right_quote);
+      else if (! buffersize && orig_buffersize)
+        {
+          /* Disable read-only scan, and reprocess to write quoted string.  */
+          buffersize = orig_buffersize;
+          len = 0;
+          goto process_input;
+        }
+    }
+
+  if (quote_string && !elide_outer_quotes)
+    for (; *quote_string; quote_string++)
+      STORE (*quote_string);
+
+  if (len < buffersize)
+    buffer[len] = '\0';
+  return len;
+
+ force_outer_quoting_style:
+  /* Don't reuse quote_these_too, since the addition of outer quotes
+     sufficiently quotes the specified characters.  */
+  if (quoting_style == shell_always_quoting_style && backslash_escapes)
+    quoting_style = shell_escape_always_quoting_style;
+  return quotearg_buffer_restyled (buffer, buffersize, arg, argsize,
+                                   quoting_style,
+                                   flags & ~QA_ELIDE_OUTER_QUOTES, NULL,
+                                   left_quote, right_quote);
+}
+
+/* Place into buffer BUFFER (of size BUFFERSIZE) a quoted version of
+   argument ARG (of size ARGSIZE), using O to control quoting.
+   If O is null, use the default.
+   Terminate the output with a null character, and return the written
+   size of the output, not counting the terminating null.
+   If BUFFERSIZE is too small to store the output string, return the
+   value that would have been returned had BUFFERSIZE been large enough.
+   If ARGSIZE is SIZE_MAX, use the string length of the argument for
+   ARGSIZE.  */
+size_t
+quotearg_buffer (char *buffer, size_t buffersize,
+                 char const *arg, size_t argsize,
+                 struct quoting_options const *o)
+{
+  struct quoting_options const *p = o ? o : &default_quoting_options;
+  int e = errno;
+  size_t r = quotearg_buffer_restyled (buffer, buffersize, arg, argsize,
+                                       p->style, p->flags, p->quote_these_too,
+                                       p->left_quote, p->right_quote);
+  errno = e;
+  return r;
+}
+
+char *
+quotearg_alloc (char const *arg, size_t argsize,
+                struct quoting_options const *o)
+{
+  return quotearg_alloc_mem (arg, argsize, NULL, o);
+}
+
+/* Like quotearg_buffer (..., ARG, ARGSIZE, O), except return newly
+   allocated storage containing the quoted string, and store the
+   resulting size into *SIZE, if non-NULL.  The result can contain
+   embedded null bytes only if ARGSIZE is not SIZE_MAX, SIZE is not
+   NULL, and set_quoting_flags has not set the null byte elision
+   flag.  */
+char *
+quotearg_alloc_mem (char const *arg, size_t argsize, size_t *size,
+                    struct quoting_options const *o)
+{
+  struct quoting_options const *p = o ? o : &default_quoting_options;
+  int e = errno;
+  /* Elide embedded null bytes if we can't return a size.  */
+  int flags = p->flags | (size ? 0 : QA_ELIDE_NULL_BYTES);
+  size_t bufsize = quotearg_buffer_restyled (0, 0, arg, argsize, p->style,
+                                             flags, p->quote_these_too,
+                                             p->left_quote,
+                                             p->right_quote) + 1;
+  char *buf = xcharalloc (bufsize);
+  quotearg_buffer_restyled (buf, bufsize, arg, argsize, p->style, flags,
+                            p->quote_these_too,
+                            p->left_quote, p->right_quote);
+  errno = e;
+  if (size)
+    *size = bufsize - 1;
+  return buf;
+}
+
+/* A storage slot with size and pointer to a value.  */
+struct slotvec
+{
+  size_t size;
+  char *val;
+};
+
+/* Preallocate a slot 0 buffer, so that the caller can always quote
+   one small component of a "memory exhausted" message in slot 0.  */
+static char slot0[256];
+static int nslots = 1;
+static struct slotvec slotvec0 = {sizeof slot0, slot0};
+static struct slotvec *slotvec = &slotvec0;
+
+void
+quotearg_free (void)
+{
+  struct slotvec *sv = slotvec;
+  int i;
+  for (i = 1; i < nslots; i++)
+    free (sv[i].val);
+  if (sv[0].val != slot0)
+    {
+      free (sv[0].val);
+      slotvec0.size = sizeof slot0;
+      slotvec0.val = slot0;
+    }
+  if (sv != &slotvec0)
+    {
+      free (sv);
+      slotvec = &slotvec0;
+    }
+  nslots = 1;
+}
+
+/* Use storage slot N to return a quoted version of argument ARG.
+   ARG is of size ARGSIZE, but if that is SIZE_MAX, ARG is a
+   null-terminated string.
+   OPTIONS specifies the quoting options.
+   The returned value points to static storage that can be
+   reused by the next call to this function with the same value of N.
+   N must be nonnegative; it is typically small, and must be
+   less than MIN (INT_MAX, IDX_MAX).  The type of N is signed
+   to allow for future extensions (using negative values).  */
+static char *
+quotearg_n_options (int n, char const *arg, size_t argsize,
+                    struct quoting_options const *options)
+{
+  int e = errno;
+
+  struct slotvec *sv = slotvec;
+
+  int nslots_max = MIN (INT_MAX, IDX_MAX);
+  if (! (0 <= n && n < nslots_max))
+    abort ();
+
+  if (nslots <= n)
+    {
+      bool preallocated = (sv == &slotvec0);
+      idx_t new_nslots = nslots;
+
+      slotvec = sv = xpalloc (preallocated ? NULL : sv, &new_nslots,
+                              n - nslots + 1, nslots_max, sizeof *sv);
+      if (preallocated)
+        *sv = slotvec0;
+      memset (sv + nslots, 0, (new_nslots - nslots) * sizeof *sv);
+      nslots = new_nslots;
+    }
+
+  {
+    size_t size = sv[n].size;
+    char *val = sv[n].val;
+    /* Elide embedded null bytes since we don't return a size.  */
+    int flags = options->flags | QA_ELIDE_NULL_BYTES;
+    size_t qsize = quotearg_buffer_restyled (val, size, arg, argsize,
+                                             options->style, flags,
+                                             options->quote_these_too,
+                                             options->left_quote,
+                                             options->right_quote);
+
+    if (size <= qsize)
+      {
+        sv[n].size = size = qsize + 1;
+        if (val != slot0)
+          free (val);
+        sv[n].val = val = xcharalloc (size);
+        quotearg_buffer_restyled (val, size, arg, argsize, options->style,
+                                  flags, options->quote_these_too,
+                                  options->left_quote,
+                                  options->right_quote);
+      }
+
+    errno = e;
+    return val;
+  }
+}
+
+char *
+quotearg_n (int n, char const *arg)
+{
+  return quotearg_n_options (n, arg, SIZE_MAX, &default_quoting_options);
+}
+
+char *
+quotearg_n_mem (int n, char const *arg, size_t argsize)
+{
+  return quotearg_n_options (n, arg, argsize, &default_quoting_options);
+}
+
+char *
+quotearg (char const *arg)
+{
+  return quotearg_n (0, arg);
+}
+
+char *
+quotearg_mem (char const *arg, size_t argsize)
+{
+  return quotearg_n_mem (0, arg, argsize);
+}
+
+char *
+quotearg_n_style (int n, enum quoting_style s, char const *arg)
+{
+  struct quoting_options const o = quoting_options_from_style (s);
+  return quotearg_n_options (n, arg, SIZE_MAX, &o);
+}
+
+char *
+quotearg_n_style_mem (int n, enum quoting_style s,
+                      char const *arg, size_t argsize)
+{
+  struct quoting_options const o = quoting_options_from_style (s);
+  return quotearg_n_options (n, arg, argsize, &o);
+}
+
+char *
+quotearg_style (enum quoting_style s, char const *arg)
+{
+  return quotearg_n_style (0, s, arg);
+}
+
+char *
+quotearg_style_mem (enum quoting_style s, char const *arg, size_t argsize)
+{
+  return quotearg_n_style_mem (0, s, arg, argsize);
+}
+
+char *
+quotearg_char_mem (char const *arg, size_t argsize, char ch)
+{
+  struct quoting_options options;
+  options = default_quoting_options;
+  set_char_quoting (&options, ch, 1);
+  return quotearg_n_options (0, arg, argsize, &options);
+}
+
+char *
+quotearg_char (char const *arg, char ch)
+{
+  return quotearg_char_mem (arg, SIZE_MAX, ch);
+}
+
+char *
+quotearg_colon (char const *arg)
+{
+  return quotearg_char (arg, ':');
+}
+
+char *
+quotearg_colon_mem (char const *arg, size_t argsize)
+{
+  return quotearg_char_mem (arg, argsize, ':');
+}
+
+char *
+quotearg_n_style_colon (int n, enum quoting_style s, char const *arg)
+{
+  struct quoting_options options;
+  options = quoting_options_from_style (s);
+  set_char_quoting (&options, ':', 1);
+  return quotearg_n_options (n, arg, SIZE_MAX, &options);
+}
+
+char *
+quotearg_n_custom (int n, char const *left_quote,
+                   char const *right_quote, char const *arg)
+{
+  return quotearg_n_custom_mem (n, left_quote, right_quote, arg,
+                                SIZE_MAX);
+}
+
+char *
+quotearg_n_custom_mem (int n, char const *left_quote,
+                       char const *right_quote,
+                       char const *arg, size_t argsize)
+{
+  struct quoting_options o = default_quoting_options;
+  set_custom_quoting (&o, left_quote, right_quote);
+  return quotearg_n_options (n, arg, argsize, &o);
+}
+
+char *
+quotearg_custom (char const *left_quote, char const *right_quote,
+                 char const *arg)
+{
+  return quotearg_n_custom (0, left_quote, right_quote, arg);
+}
+
+char *
+quotearg_custom_mem (char const *left_quote, char const *right_quote,
+                     char const *arg, size_t argsize)
+{
+  return quotearg_n_custom_mem (0, left_quote, right_quote, arg,
+                                argsize);
+}
+
+
+/* The quoting option used by the functions of quote.h.  */
+struct quoting_options quote_quoting_options =
+  {
+    locale_quoting_style,
+    0,
+    { 0 },
+    NULL, NULL
+  };
+
+char const *
+quote_n_mem (int n, char const *arg, size_t argsize)
+{
+  return quotearg_n_options (n, arg, argsize, &quote_quoting_options);
+}
+
+char const *
+quote_mem (char const *arg, size_t argsize)
+{
+  return quote_n_mem (0, arg, argsize);
+}
+
+char const *
+quote_n (int n, char const *arg)
+{
+  return quote_n_mem (n, arg, SIZE_MAX);
+}
+
+char const *
+quote (char const *arg)
+{
+  return quote_n (0, arg);
+}
+
+/*
+ * Hey Emacs!
+ * Local Variables:
+ * coding: utf-8
+ * End:
+ */