NeoMutt  2022-04-29-247-gc6aae8
Teaching an old dog new tricks
DOXYGEN
rfc3676.c
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1
32#include "config.h"
33#include <stdbool.h>
34#include <stdio.h>
35#include <unistd.h>
36#include "mutt/lib.h"
37#include "config/lib.h"
38#include "email/lib.h"
39#include "core/lib.h"
40#include "gui/lib.h"
41#include "rfc3676.h"
42#include "muttlib.h"
43
44#define FLOWED_MAX 72
45
50{
51 size_t width;
52 size_t spaces;
53 bool delsp;
54};
55
61static int get_quote_level(const char *line)
62{
63 int quoted = 0;
64 const char *p = line;
65
66 while (p && (*p == '>'))
67 {
68 quoted++;
69 p++;
70 }
71
72 return quoted;
73}
74
85static int space_quotes(struct State *s)
86{
87 /* Allow quote spacing in the pager even for `$text_flowed`,
88 * but obviously not when replying. */
89 const bool c_text_flowed = cs_subset_bool(NeoMutt->sub, "text_flowed");
90 if (c_text_flowed && (s->flags & MUTT_REPLYING))
91 return 0;
92
93 const bool c_reflow_space_quotes = cs_subset_bool(NeoMutt->sub, "reflow_space_quotes");
94 return c_reflow_space_quotes;
95}
96
108static bool add_quote_suffix(struct State *s, int ql)
109{
110 if (s->flags & MUTT_REPLYING)
111 return false;
112
113 if (space_quotes(s))
114 return false;
115
116 if (!ql && !s->prefix)
117 return false;
118
119 /* The prefix will add its own space */
120 const bool c_text_flowed = cs_subset_bool(NeoMutt->sub, "text_flowed");
121 if (!c_text_flowed && !ql && s->prefix)
122 return false;
123
124 return true;
125}
126
134static size_t print_indent(int ql, struct State *s, int add_suffix)
135{
136 size_t wid = 0;
137
138 if (s->prefix)
139 {
140 /* use given prefix only for format=fixed replies to format=flowed,
141 * for format=flowed replies to format=flowed, use '>' indentation */
142 const bool c_text_flowed = cs_subset_bool(NeoMutt->sub, "text_flowed");
143 if (c_text_flowed)
144 ql++;
145 else
146 {
147 state_puts(s, s->prefix);
148 wid = mutt_strwidth(s->prefix);
149 }
150 }
151 for (int i = 0; i < ql; i++)
152 {
153 state_putc(s, '>');
154 if (space_quotes(s))
155 state_putc(s, ' ');
156 }
157 if (add_suffix)
158 state_putc(s, ' ');
159
160 if (space_quotes(s))
161 ql *= 2;
162
163 return ql + add_suffix + wid;
164}
165
171static void flush_par(struct State *s, struct FlowedState *fst)
172{
173 if (fst->width > 0)
174 {
175 state_putc(s, '\n');
176 fst->width = 0;
177 }
178 fst->spaces = 0;
179}
180
190static int quote_width(struct State *s, int ql)
191{
192 const int screen_width = (s->flags & MUTT_DISPLAY) ? s->wraplen : 80;
193 const short c_reflow_wrap = cs_subset_number(NeoMutt->sub, "reflow_wrap");
194 int width = mutt_window_wrap_cols(screen_width, c_reflow_wrap);
195 const bool c_text_flowed = cs_subset_bool(NeoMutt->sub, "text_flowed");
196 if (c_text_flowed && (s->flags & MUTT_REPLYING))
197 {
198 /* When replying, force a wrap at FLOWED_MAX to comply with RFC3676
199 * guidelines */
200 if (width > FLOWED_MAX)
201 width = FLOWED_MAX;
202 ql++; /* When replying, we will add an additional quote level */
203 }
204 /* adjust the paragraph width subtracting the number of prefix chars */
205 width -= space_quotes(s) ? ql * 2 : ql;
206 /* When displaying (not replying), there may be a space between the prefix
207 * string and the paragraph */
208 if (add_quote_suffix(s, ql))
209 width--;
210 /* failsafe for really long quotes */
211 if (width <= 0)
212 width = FLOWED_MAX; /* arbitrary, since the line will wrap */
213 return width;
214}
215
224static void print_flowed_line(char *line, struct State *s, int ql,
225 struct FlowedState *fst, bool term)
226{
227 size_t width, w, words = 0;
228 char *p = NULL;
229 char last;
230
231 if (!line || (*line == '\0'))
232 {
233 /* flush current paragraph (if any) first */
234 flush_par(s, fst);
235 print_indent(ql, s, 0);
236 state_putc(s, '\n');
237 return;
238 }
239
240 width = quote_width(s, ql);
241 last = line[mutt_str_len(line) - 1];
242
243 mutt_debug(LL_DEBUG5, "f=f: line [%s], width = %ld, spaces = %lu\n", line,
244 (long) width, fst->spaces);
245
246 for (words = 0; (p = mutt_str_sep(&line, " "));)
247 {
248 mutt_debug(LL_DEBUG5, "f=f: word [%s], width: %lu, remaining = [%s]\n", p,
249 fst->width, line);
250
251 /* remember number of spaces */
252 if (*p == '\0')
253 {
254 mutt_debug(LL_DEBUG3, "f=f: additional space\n");
255 fst->spaces++;
256 continue;
257 }
258 /* there's exactly one space prior to every but the first word */
259 if (words)
260 fst->spaces++;
261
262 w = mutt_strwidth(p);
263 /* see if we need to break the line but make sure the first word is put on
264 * the line regardless; if for DelSp=yes only one trailing space is used,
265 * we probably have a long word that we should break within (we leave that
266 * up to the pager or user) */
267 if (!(!fst->spaces && fst->delsp && (last != ' ')) && (w < width) &&
268 (w + fst->width + fst->spaces > width))
269 {
270 mutt_debug(LL_DEBUG3, "f=f: break line at %lu, %lu spaces left\n",
271 fst->width, fst->spaces);
272 /* only honor trailing spaces for format=flowed replies */
273 const bool c_text_flowed = cs_subset_bool(NeoMutt->sub, "text_flowed");
274 if (c_text_flowed)
275 for (; fst->spaces; fst->spaces--)
276 state_putc(s, ' ');
277 state_putc(s, '\n');
278 fst->width = 0;
279 fst->spaces = 0;
280 words = 0;
281 }
282
283 if (!words && !fst->width)
284 fst->width = print_indent(ql, s, add_quote_suffix(s, ql));
285 fst->width += w + fst->spaces;
286 for (; fst->spaces; fst->spaces--)
287 state_putc(s, ' ');
288 state_puts(s, p);
289 words++;
290 }
291
292 if (term)
293 flush_par(s, fst);
294}
295
303static void print_fixed_line(const char *line, struct State *s, int ql, struct FlowedState *fst)
304{
305 print_indent(ql, s, add_quote_suffix(s, ql));
306 if (line && *line)
307 state_puts(s, line);
308 state_putc(s, '\n');
309
310 fst->width = 0;
311 fst->spaces = 0;
312}
313
318int rfc3676_handler(struct Body *a, struct State *s)
319{
320 char *buf = NULL;
321 unsigned int quotelevel = 0;
322 bool delsp = false;
323 size_t sz = 0;
324 struct FlowedState fst = { 0 };
325
326 /* respect DelSp of RFC3676 only with f=f parts */
327 char *t = mutt_param_get(&a->parameter, "delsp");
328 if (t)
329 {
330 delsp = mutt_istr_equal(t, "yes");
331 t = NULL;
332 fst.delsp = true;
333 }
334
335 mutt_debug(LL_DEBUG3, "f=f: DelSp: %s\n", delsp ? "yes" : "no");
336
337 while ((buf = mutt_file_read_line(buf, &sz, s->fp_in, NULL, MUTT_RL_NO_FLAGS)))
338 {
339 const size_t buf_len = mutt_str_len(buf);
340 const unsigned int newql = get_quote_level(buf);
341
342 /* end flowed paragraph (if we're within one) if quoting level
343 * changes (should not but can happen, see RFC3676, sec. 4.5.) */
344 if (newql != quotelevel)
345 flush_par(s, &fst);
346
347 quotelevel = newql;
348 int buf_off = newql;
349
350 /* respect sender's space-stuffing by removing one leading space */
351 if (buf[buf_off] == ' ')
352 buf_off++;
353
354 /* test for signature separator */
355 const unsigned int sigsep = mutt_str_equal(buf + buf_off, "-- ");
356
357 /* a fixed line either has no trailing space or is the
358 * signature separator */
359 const bool fixed = (buf_len == buf_off) || (buf[buf_len - 1] != ' ') || sigsep;
360
361 /* print fixed-and-standalone, fixed-and-empty and sigsep lines as
362 * fixed lines */
363 if ((fixed && ((fst.width == 0) || (buf_len == 0))) || sigsep)
364 {
365 /* if we're within a flowed paragraph, terminate it */
366 flush_par(s, &fst);
367 print_fixed_line(buf + buf_off, s, quotelevel, &fst);
368 continue;
369 }
370
371 /* for DelSp=yes, we need to strip one SP prior to CRLF on flowed lines */
372 if (delsp && !fixed)
373 buf[buf_len - 1] = '\0';
374
375 print_flowed_line(buf + buf_off, s, quotelevel, &fst, fixed);
376 }
377
378 flush_par(s, &fst);
379
380 FREE(&buf);
381 return 0;
382}
383
390{
391 if (b && (b->type == TYPE_TEXT) && mutt_istr_equal("plain", b->subtype))
392 {
393 const char *format = mutt_param_get(&b->parameter, "format");
394 if (mutt_istr_equal("flowed", format))
395 return true;
396 }
397
398 return false;
399}
400
414static void rfc3676_space_stuff(const char *filename, bool unstuff)
415{
416 FILE *fp_out = NULL;
417 char *buf = NULL;
418 size_t blen = 0;
419
420 struct Buffer *tmpfile = mutt_buffer_pool_get();
421
422 FILE *fp_in = mutt_file_fopen(filename, "r");
423 if (!fp_in)
424 goto bail;
425
426 mutt_buffer_mktemp(tmpfile);
427 fp_out = mutt_file_fopen(mutt_buffer_string(tmpfile), "w+");
428 if (!fp_out)
429 goto bail;
430
431 while ((buf = mutt_file_read_line(buf, &blen, fp_in, NULL, MUTT_RL_NO_FLAGS)) != NULL)
432 {
433 if (unstuff)
434 {
435 if (buf[0] == ' ')
436 fputs(buf + 1, fp_out);
437 else
438 fputs(buf, fp_out);
439 }
440 else
441 {
442 if ((buf[0] == ' ') || mutt_str_startswith(buf, "From "))
443 fputc(' ', fp_out);
444 fputs(buf, fp_out);
445 }
446 fputc('\n', fp_out);
447 }
448 FREE(&buf);
449 mutt_file_fclose(&fp_in);
450 mutt_file_fclose(&fp_out);
451 mutt_file_set_mtime(filename, mutt_buffer_string(tmpfile));
452
453 fp_in = mutt_file_fopen(mutt_buffer_string(tmpfile), "r");
454 if (!fp_in)
455 goto bail;
456
457 if ((truncate(filename, 0) == -1) || ((fp_out = mutt_file_fopen(filename, "a")) == NULL))
458 {
459 mutt_perror(filename);
460 goto bail;
461 }
462
463 mutt_file_copy_stream(fp_in, fp_out);
464 mutt_file_set_mtime(mutt_buffer_string(tmpfile), filename);
465 unlink(mutt_buffer_string(tmpfile));
466
467bail:
468 mutt_file_fclose(&fp_in);
469 mutt_file_fclose(&fp_out);
470 mutt_buffer_pool_release(&tmpfile);
471}
472
482{
483 if (!e || !e->body || !e->body->filename)
484 return;
485
488}
489
495{
496 if (!e || !e->body || !e->body->filename)
497 return;
498
501}
502
513void mutt_rfc3676_space_unstuff_attachment(struct Body *b, const char *filename)
514{
515 if (!filename)
516 return;
517
519 return;
520
521 rfc3676_space_stuff(filename, true);
522}
523
534void mutt_rfc3676_space_stuff_attachment(struct Body *b, const char *filename)
535{
536 if (!filename)
537 return;
538
540 return;
541
542 rfc3676_space_stuff(filename, false);
543}
static const char * mutt_buffer_string(const struct Buffer *buf)
Convert a buffer to a const char * "string".
Definition: buffer.h:77
short cs_subset_number(const struct ConfigSubset *sub, const char *name)
Get a number config item by name.
Definition: helpers.c:169
bool cs_subset_bool(const struct ConfigSubset *sub, const char *name)
Get a boolean config item by name.
Definition: helpers.c:73
Convenience wrapper for the config headers.
Convenience wrapper for the core headers.
size_t mutt_strwidth(const char *s)
Measure a string's width in screen cells.
Definition: curs_lib.c:907
Structs that make up an email.
int mutt_file_copy_stream(FILE *fp_in, FILE *fp_out)
Copy the contents of one file into another.
Definition: file.c:260
char * mutt_file_read_line(char *line, size_t *size, FILE *fp, int *line_num, ReadLineFlags flags)
Read a line from a file.
Definition: file.c:720
FILE * mutt_file_fopen(const char *path, const char *mode)
Call fopen() safely.
Definition: file.c:618
int mutt_file_fclose(FILE **fp)
Close a FILE handle (and NULL the pointer)
Definition: file.c:152
void mutt_file_set_mtime(const char *from, const char *to)
Set the modification time of one file from another.
Definition: file.c:1059
#define MUTT_RL_NO_FLAGS
No flags are set.
Definition: file.h:38
int rfc3676_handler(struct Body *a, struct State *s)
Body handler implementing RFC3676 for format=flowed - Implements handler_t -.
Definition: rfc3676.c:318
#define mutt_debug(LEVEL,...)
Definition: logging.h:84
#define mutt_perror(...)
Definition: logging.h:88
Convenience wrapper for the gui headers.
@ LL_DEBUG3
Log at debug level 3.
Definition: logging.h:42
@ LL_DEBUG5
Log at debug level 5.
Definition: logging.h:44
#define FREE(x)
Definition: memory.h:43
@ TYPE_TEXT
Type: 'text/*'.
Definition: mime.h:38
Convenience wrapper for the library headers.
#define state_puts(STATE, STR)
Definition: state.h:56
#define state_putc(STATE, STR)
Definition: state.h:57
#define MUTT_DISPLAY
Output is displayed to the user.
Definition: state.h:32
#define MUTT_REPLYING
Are we replying?
Definition: state.h:38
bool mutt_istr_equal(const char *a, const char *b)
Compare two strings, ignoring case.
Definition: string.c:819
bool mutt_str_equal(const char *a, const char *b)
Compare two strings.
Definition: string.c:807
size_t mutt_str_startswith(const char *str, const char *prefix)
Check whether a string starts with a prefix.
Definition: string.c:227
size_t mutt_str_len(const char *a)
Calculate the length of a string, safely.
Definition: string.c:567
char * mutt_str_sep(char **stringp, const char *delim)
Find first occurance of any of delim characters in *stringp.
Definition: string.c:183
int mutt_window_wrap_cols(int width, short wrap)
Calculate the wrap column for a given screen width.
Definition: mutt_window.c:365
Some miscellaneous functions.
#define mutt_buffer_mktemp(buf)
Definition: muttlib.h:74
char * mutt_param_get(const struct ParameterList *pl, const char *s)
Find a matching Parameter.
Definition: parameter.c:84
void mutt_buffer_pool_release(struct Buffer **pbuf)
Free a Buffer from the pool.
Definition: pool.c:112
struct Buffer * mutt_buffer_pool_get(void)
Get a Buffer from the pool.
Definition: pool.c:101
static void rfc3676_space_stuff(const char *filename, bool unstuff)
Perform required RFC3676 space stuffing.
Definition: rfc3676.c:414
#define FLOWED_MAX
Definition: rfc3676.c:44
void mutt_rfc3676_space_unstuff(struct Email *e)
Remove RFC3676 space stuffing.
Definition: rfc3676.c:494
static bool add_quote_suffix(struct State *s, int ql)
Should we add a trailing space to quotes.
Definition: rfc3676.c:108
static void print_fixed_line(const char *line, struct State *s, int ql, struct FlowedState *fst)
Print a fixed format line.
Definition: rfc3676.c:303
void mutt_rfc3676_space_stuff_attachment(struct Body *b, const char *filename)
Stuff attachments.
Definition: rfc3676.c:534
static void print_flowed_line(char *line, struct State *s, int ql, struct FlowedState *fst, bool term)
Print a format-flowed line.
Definition: rfc3676.c:224
static int get_quote_level(const char *line)
Get the quote level of a line.
Definition: rfc3676.c:61
void mutt_rfc3676_space_unstuff_attachment(struct Body *b, const char *filename)
Unstuff attachments.
Definition: rfc3676.c:513
static size_t print_indent(int ql, struct State *s, int add_suffix)
Print indented text.
Definition: rfc3676.c:134
static int space_quotes(struct State *s)
Should we add spaces between quote levels.
Definition: rfc3676.c:85
bool mutt_rfc3676_is_format_flowed(struct Body *b)
Is the Email "format-flowed"?
Definition: rfc3676.c:389
void mutt_rfc3676_space_stuff(struct Email *e)
Perform RFC3676 space stuffing on an Email.
Definition: rfc3676.c:481
static int quote_width(struct State *s, int ql)
Calculate the paragraph width based upon the quote level.
Definition: rfc3676.c:190
static void flush_par(struct State *s, struct FlowedState *fst)
Write out the paragraph.
Definition: rfc3676.c:171
RFC3676 Format Flowed routines.
The body of an email.
Definition: body.h:36
struct ParameterList parameter
Parameters of the content-type.
Definition: body.h:62
char * subtype
content-type subtype
Definition: body.h:60
unsigned int type
content-type primary type, ContentType
Definition: body.h:40
char * filename
When sending a message, this is the file to which this structure refers.
Definition: body.h:58
String manipulation buffer.
Definition: buffer.h:34
The envelope/body of an email.
Definition: email.h:37
struct Body * body
List of MIME parts.
Definition: email.h:67
State of a Format-Flowed line of text.
Definition: rfc3676.c:50
bool delsp
Definition: rfc3676.c:53
size_t width
Definition: rfc3676.c:51
size_t spaces
Definition: rfc3676.c:52
Container for Accounts, Notifications.
Definition: neomutt.h:37
struct ConfigSubset * sub
Inherited config items.
Definition: neomutt.h:39
Keep track when processing files.
Definition: state.h:46
int wraplen
Width to wrap lines to (when flags & MUTT_DISPLAY)
Definition: state.h:51
StateFlags flags
Flags, e.g. MUTT_DISPLAY.
Definition: state.h:50
char * prefix
String to add to the beginning of each output line.
Definition: state.h:49
FILE * fp_in
File to read from.
Definition: state.h:47