NeoMutt  2020-06-26-250-g349c94
Teaching an old dog new tricks
DOXYGEN
rfc3676.c
Go to the documentation of this file.
1 
32 #include "config.h"
33 #include <stdbool.h>
34 #include <stdio.h>
35 #include <string.h>
36 #include <unistd.h>
37 #include "mutt/lib.h"
38 #include "email/lib.h"
39 #include "gui/lib.h"
40 #include "rfc3676.h"
41 #include "mutt_globals.h"
42 #include "muttlib.h"
43 #include "state.h"
44 
45 /* These Config Variables are only used in rfc3676.c */
47 short C_ReflowWrap;
48 
49 #define FLOWED_MAX 72
50 
55 {
56  size_t width;
57  size_t spaces;
58  bool delsp;
59 };
60 
66 static int get_quote_level(const char *line)
67 {
68  int quoted = 0;
69  const char *p = line;
70 
71  while (p && (*p == '>'))
72  {
73  quoted++;
74  p++;
75  }
76 
77  return quoted;
78 }
79 
90 static int space_quotes(struct State *s)
91 {
92  /* Allow quote spacing in the pager even for C_TextFlowed,
93  * but obviously not when replying. */
94  if (C_TextFlowed && (s->flags & MUTT_REPLYING))
95  return 0;
96 
97  return C_ReflowSpaceQuotes;
98 }
99 
111 static bool add_quote_suffix(struct State *s, int ql)
112 {
113  if (s->flags & MUTT_REPLYING)
114  return false;
115 
116  if (space_quotes(s))
117  return false;
118 
119  if (!ql && !s->prefix)
120  return false;
121 
122  /* The prefix will add its own space */
123  if (!C_TextFlowed && !ql && s->prefix)
124  return false;
125 
126  return true;
127 }
128 
136 static size_t print_indent(int ql, struct State *s, int add_suffix)
137 {
138  size_t wid = 0;
139 
140  if (s->prefix)
141  {
142  /* use given prefix only for format=fixed replies to format=flowed,
143  * for format=flowed replies to format=flowed, use '>' indentation */
144  if (C_TextFlowed)
145  ql++;
146  else
147  {
148  state_puts(s, s->prefix);
149  wid = mutt_strwidth(s->prefix);
150  }
151  }
152  for (int i = 0; i < ql; i++)
153  {
154  state_putc(s, '>');
155  if (space_quotes(s))
156  state_putc(s, ' ');
157  }
158  if (add_suffix)
159  state_putc(s, ' ');
160 
161  if (space_quotes(s))
162  ql *= 2;
163 
164  return ql + add_suffix + wid;
165 }
166 
172 static void flush_par(struct State *s, struct FlowedState *fst)
173 {
174  if (fst->width > 0)
175  {
176  state_putc(s, '\n');
177  fst->width = 0;
178  }
179  fst->spaces = 0;
180 }
181 
191 static int quote_width(struct State *s, int ql)
192 {
193  const int screen_width = (s->flags & MUTT_DISPLAY) ? s->wraplen : 80;
194  int width = mutt_window_wrap_cols(screen_width, C_ReflowWrap);
195  if (C_TextFlowed && (s->flags & MUTT_REPLYING))
196  {
197  /* When replying, force a wrap at FLOWED_MAX to comply with RFC3676
198  * guidelines */
199  if (width > FLOWED_MAX)
200  width = FLOWED_MAX;
201  ql++; /* When replying, we will add an additional quote level */
202  }
203  /* adjust the paragraph width subtracting the number of prefix chars */
204  width -= space_quotes(s) ? ql * 2 : ql;
205  /* When displaying (not replying), there may be a space between the prefix
206  * string and the paragraph */
207  if (add_quote_suffix(s, ql))
208  width--;
209  /* failsafe for really long quotes */
210  if (width <= 0)
211  width = FLOWED_MAX; /* arbitrary, since the line will wrap */
212  return width;
213 }
214 
223 static void print_flowed_line(char *line, struct State *s, int ql,
224  struct FlowedState *fst, bool term)
225 {
226  size_t width, w, words = 0;
227  char *p = NULL;
228  char last;
229 
230  if (!line || (*line == '\0'))
231  {
232  /* flush current paragraph (if any) first */
233  flush_par(s, fst);
234  print_indent(ql, s, 0);
235  state_putc(s, '\n');
236  return;
237  }
238 
239  width = quote_width(s, ql);
240  last = line[mutt_str_len(line) - 1];
241 
242  mutt_debug(LL_DEBUG5, "f=f: line [%s], width = %ld, spaces = %lu\n", line,
243  (long) width, fst->spaces);
244 
245  for (words = 0; (p = strsep(&line, " "));)
246  {
247  mutt_debug(LL_DEBUG5, "f=f: word [%s], width: %lu, remaining = [%s]\n", p,
248  fst->width, line);
249 
250  /* remember number of spaces */
251  if (*p == '\0')
252  {
253  mutt_debug(LL_DEBUG3, "f=f: additional space\n");
254  fst->spaces++;
255  continue;
256  }
257  /* there's exactly one space prior to every but the first word */
258  if (words)
259  fst->spaces++;
260 
261  w = mutt_strwidth(p);
262  /* see if we need to break the line but make sure the first word is put on
263  * the line regardless; if for DelSp=yes only one trailing space is used,
264  * we probably have a long word that we should break within (we leave that
265  * up to the pager or user) */
266  if (!(!fst->spaces && fst->delsp && (last != ' ')) && (w < width) &&
267  (w + fst->width + fst->spaces > width))
268  {
269  mutt_debug(LL_DEBUG3, "f=f: break line at %lu, %lu spaces left\n",
270  fst->width, fst->spaces);
271  /* only honor trailing spaces for format=flowed replies */
272  if (C_TextFlowed)
273  for (; fst->spaces; fst->spaces--)
274  state_putc(s, ' ');
275  state_putc(s, '\n');
276  fst->width = 0;
277  fst->spaces = 0;
278  words = 0;
279  }
280 
281  if (!words && !fst->width)
282  fst->width = print_indent(ql, s, add_quote_suffix(s, ql));
283  fst->width += w + fst->spaces;
284  for (; fst->spaces; fst->spaces--)
285  state_putc(s, ' ');
286  state_puts(s, p);
287  words++;
288  }
289 
290  if (term)
291  flush_par(s, fst);
292 }
293 
301 static void print_fixed_line(const char *line, struct State *s, int ql, struct FlowedState *fst)
302 {
303  print_indent(ql, s, add_quote_suffix(s, ql));
304  if (line && *line)
305  state_puts(s, line);
306  state_putc(s, '\n');
307 
308  fst->width = 0;
309  fst->spaces = 0;
310 }
311 
316 int rfc3676_handler(struct Body *a, struct State *s)
317 {
318  char *buf = NULL;
319  unsigned int quotelevel = 0;
320  bool delsp = false;
321  size_t sz = 0;
322  struct FlowedState fst = { 0 };
323 
324  /* respect DelSp of RFC3676 only with f=f parts */
325  char *t = mutt_param_get(&a->parameter, "delsp");
326  if (t)
327  {
328  delsp = mutt_istr_equal(t, "yes");
329  t = NULL;
330  fst.delsp = true;
331  }
332 
333  mutt_debug(LL_DEBUG3, "f=f: DelSp: %s\n", delsp ? "yes" : "no");
334 
335  while ((buf = mutt_file_read_line(buf, &sz, s->fp_in, NULL, 0)))
336  {
337  const size_t buf_len = mutt_str_len(buf);
338  const unsigned int newql = get_quote_level(buf);
339 
340  /* end flowed paragraph (if we're within one) if quoting level
341  * changes (should not but can happen, see RFC3676, sec. 4.5.) */
342  if (newql != quotelevel)
343  flush_par(s, &fst);
344 
345  quotelevel = newql;
346  int buf_off = newql;
347 
348  /* respect sender's space-stuffing by removing one leading space */
349  if (buf[buf_off] == ' ')
350  buf_off++;
351 
352  /* test for signature separator */
353  const unsigned int sigsep = mutt_str_equal(buf + buf_off, "-- ");
354 
355  /* a fixed line either has no trailing space or is the
356  * signature separator */
357  const bool fixed = (buf_len == buf_off) || (buf[buf_len - 1] != ' ') || sigsep;
358 
359  /* print fixed-and-standalone, fixed-and-empty and sigsep lines as
360  * fixed lines */
361  if ((fixed && ((fst.width == 0) || (buf_len == 0))) || sigsep)
362  {
363  /* if we're within a flowed paragraph, terminate it */
364  flush_par(s, &fst);
365  print_fixed_line(buf + buf_off, s, quotelevel, &fst);
366  continue;
367  }
368 
369  /* for DelSp=yes, we need to strip one SP prior to CRLF on flowed lines */
370  if (delsp && !fixed)
371  buf[buf_len - 1] = '\0';
372 
373  print_flowed_line(buf + buf_off, s, quotelevel, &fst, fixed);
374  }
375 
376  flush_par(s, &fst);
377 
378  FREE(&buf);
379  return 0;
380 }
381 
388 {
389  if (b && (b->type == TYPE_TEXT) && mutt_istr_equal("plain", b->subtype))
390  {
391  const char *format = mutt_param_get(&b->parameter, "format");
392  if (mutt_istr_equal("flowed", format))
393  return true;
394  }
395 
396  return false;
397 }
398 
412 static void rfc3676_space_stuff(const char *filename, bool unstuff)
413 {
414  FILE *fp_out = NULL;
415  char *buf = NULL;
416  size_t blen = 0;
417 
418  struct Buffer *tmpfile = mutt_buffer_pool_get();
419 
420  FILE *fp_in = mutt_file_fopen(filename, "r");
421  if (!fp_in)
422  goto bail;
423 
424  mutt_buffer_mktemp(tmpfile);
425  fp_out = mutt_file_fopen(mutt_b2s(tmpfile), "w+");
426  if (!fp_out)
427  goto bail;
428 
429  while ((buf = mutt_file_read_line(buf, &blen, fp_in, NULL, 0)) != NULL)
430  {
431  if (unstuff)
432  {
433  if (buf[0] == ' ')
434  fputs(buf + 1, fp_out);
435  else
436  fputs(buf, fp_out);
437  }
438  else
439  {
440  if ((buf[0] == ' ') || mutt_str_startswith(buf, "From "))
441  fputc(' ', fp_out);
442  fputs(buf, fp_out);
443  }
444  fputc('\n', fp_out);
445  }
446  FREE(&buf);
447  mutt_file_fclose(&fp_in);
448  mutt_file_fclose(&fp_out);
449  mutt_file_set_mtime(filename, mutt_b2s(tmpfile));
450 
451  fp_in = mutt_file_fopen(mutt_b2s(tmpfile), "r");
452  if (!fp_in)
453  goto bail;
454 
455  if ((truncate(filename, 0) == -1) || ((fp_out = mutt_file_fopen(filename, "a")) == NULL))
456  {
457  mutt_perror(filename);
458  goto bail;
459  }
460 
461  mutt_file_copy_stream(fp_in, fp_out);
462  mutt_file_set_mtime(mutt_b2s(tmpfile), filename);
463  unlink(mutt_b2s(tmpfile));
464 
465 bail:
466  mutt_file_fclose(&fp_in);
467  mutt_file_fclose(&fp_out);
468  mutt_buffer_pool_release(&tmpfile);
469 }
470 
480 {
481  if (!e || !e->content || !e->content->filename)
482  return;
483 
486 }
487 
493 {
494  if (!e || !e->content || !e->content->filename)
495  return;
496 
499 }
500 
511 void mutt_rfc3676_space_unstuff_attachment(struct Body *b, const char *filename)
512 {
513  if (!filename)
514  return;
515 
516  if (b && !mutt_rfc3676_is_format_flowed(b))
517  return;
518 
519  rfc3676_space_stuff(filename, true);
520 }
521 
532 void mutt_rfc3676_space_stuff_attachment(struct Body *b, const char *filename)
533 {
534  if (!filename)
535  return;
536 
537  if (b && !mutt_rfc3676_is_format_flowed(b))
538  return;
539 
540  rfc3676_space_stuff(filename, false);
541 }
bool mutt_str_equal(const char *a, const char *b)
Compare two strings.
Definition: string.c:876
Convenience wrapper for the gui headers.
#define mutt_buffer_mktemp(buf)
Definition: muttlib.h:77
#define MUTT_DISPLAY
Output is displayed to the user.
Definition: state.h:32
char * filename
when sending a message, this is the file to which this structure refers
Definition: body.h:46
The envelope/body of an email.
Definition: email.h:37
#define state_puts(STATE, STR)
Definition: state.h:55
struct Buffer * mutt_buffer_pool_get(void)
Get a Buffer from the pool.
Definition: pool.c:101
#define mutt_perror(...)
Definition: logging.h:85
bool mutt_rfc3676_is_format_flowed(struct Body *b)
Is the Email "format-flowed"?
Definition: rfc3676.c:387
void mutt_file_set_mtime(const char *from, const char *to)
Set the modification time of one file from another.
Definition: file.c:1003
Structs that make up an email.
static bool add_quote_suffix(struct State *s, int ql)
Should we add a trailing space to quotes.
Definition: rfc3676.c:111
static int space_quotes(struct State *s)
Should we add spaces between quote levels.
Definition: rfc3676.c:90
void mutt_buffer_pool_release(struct Buffer **pbuf)
Free a Buffer from the pool.
Definition: pool.c:112
struct Body * content
List of MIME parts.
Definition: email.h:91
static int quote_width(struct State *s, int ql)
Calculate the paragraph width based upon the quote level.
Definition: rfc3676.c:191
String manipulation buffer.
Definition: buffer.h:33
char * prefix
String to add to the beginning of each output line.
Definition: state.h:48
char * mutt_file_read_line(char *line, size_t *size, FILE *fp, int *line_num, int flags)
Read a line from a file.
Definition: file.c:667
size_t spaces
Definition: rfc3676.c:57
FILE * fp_in
File to read from.
Definition: state.h:46
The body of an email.
Definition: body.h:34
Some miscellaneous functions.
StateFlags flags
Flags, e.g. MUTT_DISPLAY.
Definition: state.h:49
int mutt_file_fclose(FILE **fp)
Close a FILE handle (and NULL the pointer)
Definition: file.c:153
void mutt_rfc3676_space_unstuff(struct Email *e)
Remove RFC3676 space stuffing.
Definition: rfc3676.c:492
int wraplen
Width to wrap lines to (when flags & MUTT_DISPLAY)
Definition: state.h:50
bool mutt_istr_equal(const char *a, const char *b)
Compare two strings, ignoring case.
Definition: string.c:888
char * subtype
content-type subtype
Definition: body.h:37
#define mutt_b2s(buf)
Definition: buffer.h:41
static size_t print_indent(int ql, struct State *s, int add_suffix)
Print indented text.
Definition: rfc3676.c:136
size_t mutt_str_startswith(const char *str, const char *prefix)
Check whether a string starts with a prefix.
Definition: string.c:165
int mutt_strwidth(const char *s)
Measure a string&#39;s width in screen cells.
Definition: curs_lib.c:1358
Type: &#39;text/*&#39;.
Definition: mime.h:38
static int get_quote_level(const char *line)
Get the quote level of a line.
Definition: rfc3676.c:66
RFC3676 Format Flowed routines.
int mutt_window_wrap_cols(int width, short wrap)
Calculate the wrap column for a given screen width.
Definition: mutt_window.c:487
void mutt_rfc3676_space_unstuff_attachment(struct Body *b, const char *filename)
Unstuff attachments.
Definition: rfc3676.c:511
static void print_fixed_line(const char *line, struct State *s, int ql, struct FlowedState *fst)
Print a fixed format line.
Definition: rfc3676.c:301
unsigned int type
content-type primary type, ContentType
Definition: body.h:65
size_t width
Definition: rfc3676.c:56
Keep track when processing files.
size_t mutt_str_len(const char *a)
Calculate the length of a string, safely.
Definition: string.c:636
State of a Format-Flowed line of text.
Definition: rfc3676.c:54
int mutt_file_copy_stream(FILE *fp_in, FILE *fp_out)
Copy the contents of one file into another.
Definition: file.c:271
void mutt_rfc3676_space_stuff(struct Email *e)
Perform RFC3676 space stuffing on an Email.
Definition: rfc3676.c:479
#define FREE(x)
Definition: memory.h:40
char * mutt_param_get(const struct ParameterList *pl, const char *s)
Find a matching Parameter.
Definition: parameter.c:84
#define FLOWED_MAX
Definition: rfc3676.c:49
#define MUTT_REPLYING
Are we replying?
Definition: state.h:38
bool C_ReflowSpaceQuotes
Config: Insert spaces into reply quotes for &#39;format=flowed&#39; messages.
Definition: rfc3676.c:46
Keep track when processing files.
Definition: state.h:44
static void flush_par(struct State *s, struct FlowedState *fst)
Write out the paragraph.
Definition: rfc3676.c:172
Hundreds of global variables to back the user variables.
#define mutt_debug(LEVEL,...)
Definition: logging.h:81
#define state_putc(STATE, STR)
Definition: state.h:56
int rfc3676_handler(struct Body *a, struct State *s)
Body handler implementing RFC3676 for format=flowed - Implements handler_t.
Definition: rfc3676.c:316
int const char int line
Definition: acutest.h:617
Log at debug level 5.
Definition: logging.h:44
Convenience wrapper for the library headers.
FILE * mutt_file_fopen(const char *path, const char *mode)
Call fopen() safely.
Definition: file.c:588
static void rfc3676_space_stuff(const char *filename, bool unstuff)
Perform required RFC3676 space stuffing.
Definition: rfc3676.c:412
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:223
bool delsp
Definition: rfc3676.c:58
struct ParameterList parameter
parameters of the content-type
Definition: body.h:39
Log at debug level 3.
Definition: logging.h:42
short C_ReflowWrap
Config: Maximum paragraph width for reformatting &#39;format=flowed&#39; text.
Definition: rfc3676.c:47
void mutt_rfc3676_space_stuff_attachment(struct Body *b, const char *filename)
Stuff attachments.
Definition: rfc3676.c:532
WHERE bool C_TextFlowed
Config: Generate &#39;format=flowed&#39; messages.
Definition: mutt_globals.h:168