xref: /dragonfly/contrib/diffutils/lib/quotearg.h (revision 926deccb)
1 /* quotearg.h - quote arguments for output
2 
3    Copyright (C) 1998-2002, 2004, 2006, 2008-2013 Free Software Foundation,
4    Inc.
5 
6    This program is free software: you can redistribute it and/or modify
7    it under the terms of the GNU General Public License as published by
8    the Free Software Foundation; either version 3 of the License, or
9    (at your option) any later version.
10 
11    This program is distributed in the hope that it will be useful,
12    but WITHOUT ANY WARRANTY; without even the implied warranty of
13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14    GNU General Public License for more details.
15 
16    You should have received a copy of the GNU General Public License
17    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
18 
19 /* Written by Paul Eggert <eggert@twinsun.com> */
20 
21 #ifndef QUOTEARG_H_
22 # define QUOTEARG_H_ 1
23 
24 # include <stddef.h>
25 
26 /* Basic quoting styles.  For each style, an example is given on the
27    input strings "simple", "\0 \t\n'\"\033?""?/\\", and "a:b", using
28    quotearg_buffer, quotearg_mem, and quotearg_colon_mem with that
29    style and the default flags and quoted characters.  Note that the
30    examples are shown here as valid C strings rather than what
31    displays on a terminal (with "??/" as a trigraph for "\\").  */
32 enum quoting_style
33   {
34     /* Output names as-is (ls --quoting-style=literal).  Can result in
35        embedded null bytes if QA_ELIDE_NULL_BYTES is not in
36        effect.
37 
38        quotearg_buffer:
39        "simple", "\0 \t\n'\"\033??/\\", "a:b"
40        quotearg:
41        "simple", " \t\n'\"\033??/\\", "a:b"
42        quotearg_colon:
43        "simple", " \t\n'\"\033??/\\", "a:b"
44     */
45     literal_quoting_style,
46 
47     /* Quote names for the shell if they contain shell metacharacters
48        or would cause ambiguous output (ls --quoting-style=shell).
49        Can result in embedded null bytes if QA_ELIDE_NULL_BYTES is not
50        in effect.
51 
52        quotearg_buffer:
53        "simple", "'\0 \t\n'\\''\"\033??/\\'", "a:b"
54        quotearg:
55        "simple", "' \t\n'\\''\"\033??/\\'", "a:b"
56        quotearg_colon:
57        "simple", "' \t\n'\\''\"\033??/\\'", "'a:b'"
58     */
59     shell_quoting_style,
60 
61     /* Quote names for the shell, even if they would normally not
62        require quoting (ls --quoting-style=shell-always).  Can result
63        in embedded null bytes if QA_ELIDE_NULL_BYTES is not in effect.
64        Behaves like shell_quoting_style if QA_ELIDE_OUTER_QUOTES is in
65        effect.
66 
67        quotearg_buffer:
68        "'simple'", "'\0 \t\n'\\''\"\033??/\\'", "'a:b'"
69        quotearg:
70        "'simple'", "' \t\n'\\''\"\033??/\\'", "'a:b'"
71        quotearg_colon:
72        "'simple'", "' \t\n'\\''\"\033??/\\'", "'a:b'"
73     */
74     shell_always_quoting_style,
75 
76     /* Quote names as for a C language string (ls --quoting-style=c).
77        Behaves like c_maybe_quoting_style if QA_ELIDE_OUTER_QUOTES is
78        in effect.  Split into consecutive strings if
79        QA_SPLIT_TRIGRAPHS.
80 
81        quotearg_buffer:
82        "\"simple\"", "\"\\0 \\t\\n'\\\"\\033??/\\\\\"", "\"a:b\""
83        quotearg:
84        "\"simple\"", "\"\\0 \\t\\n'\\\"\\033??/\\\\\"", "\"a:b\""
85        quotearg_colon:
86        "\"simple\"", "\"\\0 \\t\\n'\\\"\\033??/\\\\\"", "\"a\\:b\""
87     */
88     c_quoting_style,
89 
90     /* Like c_quoting_style except omit the surrounding double-quote
91        characters if no quoted characters are encountered.
92 
93        quotearg_buffer:
94        "simple", "\"\\0 \\t\\n'\\\"\\033??/\\\\\"", "a:b"
95        quotearg:
96        "simple", "\"\\0 \\t\\n'\\\"\\033??/\\\\\"", "a:b"
97        quotearg_colon:
98        "simple", "\"\\0 \\t\\n'\\\"\\033??/\\\\\"", "\"a:b\""
99     */
100     c_maybe_quoting_style,
101 
102     /* Like c_quoting_style except always omit the surrounding
103        double-quote characters and ignore QA_SPLIT_TRIGRAPHS
104        (ls --quoting-style=escape).
105 
106        quotearg_buffer:
107        "simple", "\\0 \\t\\n'\"\\033??/\\\\", "a:b"
108        quotearg:
109        "simple", "\\0 \\t\\n'\"\\033??/\\\\", "a:b"
110        quotearg_colon:
111        "simple", "\\0 \\t\\n'\"\\033??/\\\\", "a\\:b"
112     */
113     escape_quoting_style,
114 
115     /* Like clocale_quoting_style, but use single quotes in the
116        default C locale or if the program does not use gettext
117        (ls --quoting-style=locale).  For UTF-8 locales, quote
118        characters will use Unicode.
119 
120        LC_MESSAGES=C
121        quotearg_buffer:
122        "`simple'", "`\\0 \\t\\n\\'\"\\033??/\\\\'", "`a:b'"
123        quotearg:
124        "`simple'", "`\\0 \\t\\n\\'\"\\033??/\\\\'", "`a:b'"
125        quotearg_colon:
126        "`simple'", "`\\0 \\t\\n\\'\"\\033??/\\\\'", "`a\\:b'"
127 
128        LC_MESSAGES=pt_PT.utf8
129        quotearg_buffer:
130        "\302\253simple\302\273",
131        "\302\253\\0 \\t\\n'\"\\033??/\\\\\302\253", "\302\253a:b\302\273"
132        quotearg:
133        "\302\253simple\302\273",
134        "\302\253\\0 \\t\\n'\"\\033??/\\\\\302\253", "\302\253a:b\302\273"
135        quotearg_colon:
136        "\302\253simple\302\273",
137        "\302\253\\0 \\t\\n'\"\\033??/\\\\\302\253", "\302\253a\\:b\302\273"
138     */
139     locale_quoting_style,
140 
141     /* Like c_quoting_style except use quotation marks appropriate for
142        the locale and ignore QA_SPLIT_TRIGRAPHS
143        (ls --quoting-style=clocale).
144 
145        LC_MESSAGES=C
146        quotearg_buffer:
147        "\"simple\"", "\"\\0 \\t\\n'\\\"\\033??/\\\\\"", "\"a:b\""
148        quotearg:
149        "\"simple\"", "\"\\0 \\t\\n'\\\"\\033??/\\\\\"", "\"a:b\""
150        quotearg_colon:
151        "\"simple\"", "\"\\0 \\t\\n'\\\"\\033??/\\\\\"", "\"a\\:b\""
152 
153        LC_MESSAGES=pt_PT.utf8
154        quotearg_buffer:
155        "\302\253simple\302\273",
156        "\302\253\\0 \\t\\n'\"\\033??/\\\\\302\253", "\302\253a:b\302\273"
157        quotearg:
158        "\302\253simple\302\273",
159        "\302\253\\0 \\t\\n'\"\\033??/\\\\\302\253", "\302\253a:b\302\273"
160        quotearg_colon:
161        "\302\253simple\302\273",
162        "\302\253\\0 \\t\\n'\"\\033??/\\\\\302\253", "\302\253a\\:b\302\273"
163     */
164     clocale_quoting_style,
165 
166     /* Like clocale_quoting_style except use the custom quotation marks
167        set by set_custom_quoting.  If custom quotation marks are not
168        set, the behavior is undefined.
169 
170        left_quote = right_quote = "'"
171        quotearg_buffer:
172        "'simple'", "'\\0 \\t\\n\\'\"\\033??/\\\\'", "'a:b'"
173        quotearg:
174        "'simple'", "'\\0 \\t\\n\\'\"\\033??/\\\\'", "'a:b'"
175        quotearg_colon:
176        "'simple'", "'\\0 \\t\\n\\'\"\\033??/\\\\'", "'a\\:b'"
177 
178        left_quote = "(" and right_quote = ")"
179        quotearg_buffer:
180        "(simple)", "(\\0 \\t\\n'\"\\033??/\\\\)", "(a:b)"
181        quotearg:
182        "(simple)", "(\\0 \\t\\n'\"\\033??/\\\\)", "(a:b)"
183        quotearg_colon:
184        "(simple)", "(\\0 \\t\\n'\"\\033??/\\\\)", "(a\\:b)"
185 
186        left_quote = ":" and right_quote = " "
187        quotearg_buffer:
188        ":simple ", ":\\0\\ \\t\\n'\"\\033??/\\\\ ", ":a:b "
189        quotearg:
190        ":simple ", ":\\0\\ \\t\\n'\"\\033??/\\\\ ", ":a:b "
191        quotearg_colon:
192        ":simple ", ":\\0\\ \\t\\n'\"\\033??/\\\\ ", ":a\\:b "
193 
194        left_quote = "\"'" and right_quote = "'\""
195        Notice that this is treated as a single level of quotes or two
196        levels where the outer quote need not be escaped within the inner
197        quotes.  For two levels where the outer quote must be escaped
198        within the inner quotes, you must use separate quotearg
199        invocations.
200        quotearg_buffer:
201        "\"'simple'\"", "\"'\\0 \\t\\n\\'\"\\033??/\\\\'\"", "\"'a:b'\""
202        quotearg:
203        "\"'simple'\"", "\"'\\0 \\t\\n\\'\"\\033??/\\\\'\"", "\"'a:b'\""
204        quotearg_colon:
205        "\"'simple'\"", "\"'\\0 \\t\\n\\'\"\\033??/\\\\'\"", "\"'a\\:b'\""
206     */
207     custom_quoting_style
208   };
209 
210 /* Flags for use in set_quoting_flags.  */
211 enum quoting_flags
212   {
213     /* Always elide null bytes from styles that do not quote them,
214        even when the length of the result is available to the
215        caller.  */
216     QA_ELIDE_NULL_BYTES = 0x01,
217 
218     /* Omit the surrounding quote characters if no escaped characters
219        are encountered.  Note that if no other character needs
220        escaping, then neither does the escape character.  */
221     QA_ELIDE_OUTER_QUOTES = 0x02,
222 
223     /* In the c_quoting_style and c_maybe_quoting_style, split ANSI
224        trigraph sequences into concatenated strings (for example,
225        "?""?/" rather than "??/", which could be confused with
226        "\\").  */
227     QA_SPLIT_TRIGRAPHS = 0x04
228   };
229 
230 /* For now, --quoting-style=literal is the default, but this may change.  */
231 # ifndef DEFAULT_QUOTING_STYLE
232 #  define DEFAULT_QUOTING_STYLE literal_quoting_style
233 # endif
234 
235 /* Names of quoting styles and their corresponding values.  */
236 extern char const *const quoting_style_args[];
237 extern enum quoting_style const quoting_style_vals[];
238 
239 struct quoting_options;
240 
241 /* The functions listed below set and use a hidden variable
242    that contains the default quoting style options.  */
243 
244 /* Allocate a new set of quoting options, with contents initially identical
245    to O if O is not null, or to the default if O is null.
246    It is the caller's responsibility to free the result.  */
247 struct quoting_options *clone_quoting_options (struct quoting_options *o);
248 
249 /* Get the value of O's quoting style.  If O is null, use the default.  */
250 enum quoting_style get_quoting_style (struct quoting_options *o);
251 
252 /* In O (or in the default if O is null),
253    set the value of the quoting style to S.  */
254 void set_quoting_style (struct quoting_options *o, enum quoting_style s);
255 
256 /* In O (or in the default if O is null),
257    set the value of the quoting options for character C to I.
258    Return the old value.  Currently, the only values defined for I are
259    0 (the default) and 1 (which means to quote the character even if
260    it would not otherwise be quoted).  C must never be a digit or a
261    letter that has special meaning after a backslash (for example, "\t"
262    for tab).  */
263 int set_char_quoting (struct quoting_options *o, char c, int i);
264 
265 /* In O (or in the default if O is null),
266    set the value of the quoting options flag to I, which can be a
267    bitwise combination of enum quoting_flags, or 0 for default
268    behavior.  Return the old value.  */
269 int set_quoting_flags (struct quoting_options *o, int i);
270 
271 /* In O (or in the default if O is null),
272    set the value of the quoting style to custom_quoting_style,
273    set the left quote to LEFT_QUOTE, and set the right quote to
274    RIGHT_QUOTE.  Each of LEFT_QUOTE and RIGHT_QUOTE must be
275    null-terminated and can be the empty string.  Because backslashes are
276    used for escaping, it does not make sense for RIGHT_QUOTE to contain
277    a backslash.  RIGHT_QUOTE must not begin with a digit or a letter
278    that has special meaning after a backslash (for example, "\t" for
279    tab).  */
280 void set_custom_quoting (struct quoting_options *o,
281                          char const *left_quote,
282                          char const *right_quote);
283 
284 /* Place into buffer BUFFER (of size BUFFERSIZE) a quoted version of
285    argument ARG (of size ARGSIZE), using O to control quoting.
286    If O is null, use the default.
287    Terminate the output with a null character, and return the written
288    size of the output, not counting the terminating null.
289    If BUFFERSIZE is too small to store the output string, return the
290    value that would have been returned had BUFFERSIZE been large enough.
291    If ARGSIZE is -1, use the string length of the argument for ARGSIZE.
292    On output, BUFFER might contain embedded null bytes if ARGSIZE was
293    not -1, the style of O does not use backslash escapes, and the
294    flags of O do not request elision of null bytes.*/
295 size_t quotearg_buffer (char *buffer, size_t buffersize,
296                         char const *arg, size_t argsize,
297                         struct quoting_options const *o);
298 
299 /* Like quotearg_buffer, except return the result in a newly allocated
300    buffer.  It is the caller's responsibility to free the result.  The
301    result will not contain embedded null bytes.  */
302 char *quotearg_alloc (char const *arg, size_t argsize,
303                       struct quoting_options const *o);
304 
305 /* Like quotearg_alloc, except that the length of the result,
306    excluding the terminating null byte, is stored into SIZE if it is
307    non-NULL.  The result might contain embedded null bytes if ARGSIZE
308    was not -1, SIZE was not NULL, the style of O does not use
309    backslash escapes, and the flags of O do not request elision of
310    null bytes.*/
311 char *quotearg_alloc_mem (char const *arg, size_t argsize,
312                           size_t *size, struct quoting_options const *o);
313 
314 /* Use storage slot N to return a quoted version of the string ARG.
315    Use the default quoting options.
316    The returned value points to static storage that can be
317    reused by the next call to this function with the same value of N.
318    N must be nonnegative.  The output of all functions in the
319    quotearg_n family are guaranteed to not contain embedded null
320    bytes.*/
321 char *quotearg_n (int n, char const *arg);
322 
323 /* Equivalent to quotearg_n (0, ARG).  */
324 char *quotearg (char const *arg);
325 
326 /* Use storage slot N to return a quoted version of the argument ARG
327    of size ARGSIZE.  This is like quotearg_n (N, ARG), except it can
328    quote null bytes.  */
329 char *quotearg_n_mem (int n, char const *arg, size_t argsize);
330 
331 /* Equivalent to quotearg_n_mem (0, ARG, ARGSIZE).  */
332 char *quotearg_mem (char const *arg, size_t argsize);
333 
334 /* Use style S and storage slot N to return a quoted version of the string ARG.
335    This is like quotearg_n (N, ARG), except that it uses S with no other
336    options to specify the quoting method.  */
337 char *quotearg_n_style (int n, enum quoting_style s, char const *arg);
338 
339 /* Use style S and storage slot N to return a quoted version of the
340    argument ARG of size ARGSIZE.  This is like quotearg_n_style
341    (N, S, ARG), except it can quote null bytes.  */
342 char *quotearg_n_style_mem (int n, enum quoting_style s,
343                             char const *arg, size_t argsize);
344 
345 /* Equivalent to quotearg_n_style (0, S, ARG).  */
346 char *quotearg_style (enum quoting_style s, char const *arg);
347 
348 /* Equivalent to quotearg_n_style_mem (0, S, ARG, ARGSIZE).  */
349 char *quotearg_style_mem (enum quoting_style s,
350                           char const *arg, size_t argsize);
351 
352 /* Like quotearg (ARG), except also quote any instances of CH.
353    See set_char_quoting for a description of acceptable CH values.  */
354 char *quotearg_char (char const *arg, char ch);
355 
356 /* Like quotearg_char (ARG, CH), except it can quote null bytes.  */
357 char *quotearg_char_mem (char const *arg, size_t argsize, char ch);
358 
359 /* Equivalent to quotearg_char (ARG, ':').  */
360 char *quotearg_colon (char const *arg);
361 
362 /* Like quotearg_colon (ARG), except it can quote null bytes.  */
363 char *quotearg_colon_mem (char const *arg, size_t argsize);
364 
365 /* Like quotearg_n_style (N, S, ARG) but with S as custom_quoting_style
366    with left quote as LEFT_QUOTE and right quote as RIGHT_QUOTE.  See
367    set_custom_quoting for a description of acceptable LEFT_QUOTE and
368    RIGHT_QUOTE values.  */
369 char *quotearg_n_custom (int n, char const *left_quote,
370                          char const *right_quote, char const *arg);
371 
372 /* Like quotearg_n_custom (N, LEFT_QUOTE, RIGHT_QUOTE, ARG) except it
373    can quote null bytes.  */
374 char *quotearg_n_custom_mem (int n, char const *left_quote,
375                              char const *right_quote,
376                              char const *arg, size_t argsize);
377 
378 /* Equivalent to quotearg_n_custom (0, LEFT_QUOTE, RIGHT_QUOTE, ARG).  */
379 char *quotearg_custom (char const *left_quote, char const *right_quote,
380                        char const *arg);
381 
382 /* Equivalent to quotearg_n_custom_mem (0, LEFT_QUOTE, RIGHT_QUOTE, ARG,
383                                         ARGSIZE).  */
384 char *quotearg_custom_mem (char const *left_quote,
385                            char const *right_quote,
386                            char const *arg, size_t argsize);
387 
388 /* Free any dynamically allocated memory.  */
389 void quotearg_free (void);
390 
391 #endif /* !QUOTEARG_H_ */
392