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gpg: Reflow long texts. 

* common/stringhelp.c (format_text): New function.
* common/t-stringhelp.c (stresc): New function.
(test_format_text): New function.  Test format_text.
* g10/tofu.c (get_trust): Use format_text to reflow long texts.
(show_statistics): Likewise.

--
Signed-off-by: Neal H. Walfield <neal@g10code.com>
This commit is contained in:
Neal H. Walfield 2015-11-23 22:20:28 +01:00
parent 5b84b0d660
commit 19362a8dd7
4 changed files with 283 additions and 4 deletions
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129
common/stringhelp.c
View File

@ -1327,3 +1327,132 @@ strtokenize (const char *string, const char *delim)
return result;
}
char *
format_text (char *text, int in_place, int target_cols, int max_cols)
{
const int do_debug = 0;
/* The character under consideration. */
char *p;
/* The start of the current line. */
char *line;
/* The last space that we saw. */
char *last_space = NULL;
int last_space_cols = 0;
int copied_last_space = 0;
if (! in_place)
text = xstrdup (text);
p = line = text;
while (1)
{
/* The number of columns including any trailing space. */
int cols;
p = p + strcspn (p, "\n ");
if (! p)
/* P now points to the NUL character. */
p = &text[strlen (text)];
if (*p == '\n')
/* Pass through any newlines. */
{
p ++;
line = p;
last_space = NULL;
last_space_cols = 0;
copied_last_space = 1;
continue;
}
/* Have a space or a NUL. Note: we don't count the trailing
space. */
cols = utf8_charcount (line, (uintptr_t) p - (uintptr_t) line);
if (cols < target_cols)
{
if (! *p)
/* Nothing left to break. */
break;
last_space = p;
last_space_cols = cols;
p ++;
/* Skip any immediately following spaces. If we break:
"... foo bar ..." between "foo" and "bar" then we want:
"... foo\nbar ...", which means that the left space has
to be the first space after foo, not the last space
before bar. */
while (*p == ' ')
p ++;
}
else
{
int cols_with_left_space;
int cols_with_right_space;
int left_penalty;
int right_penalty;
cols_with_left_space = last_space_cols;
cols_with_right_space = cols;
if (do_debug)
log_debug ("Breaking: '%.*s'\n",
(int) ((uintptr_t) p - (uintptr_t) line), line);
/* The number of columns away from TARGET_COLS. We prefer
to underflow than to overflow. */
left_penalty = target_cols - cols_with_left_space;
right_penalty = 2 * (cols_with_right_space - target_cols);
if (cols_with_right_space > max_cols)
/* Add a large penalty for each column that exceeds
max_cols. */
right_penalty += 4 * (cols_with_right_space - max_cols);
if (do_debug)
log_debug ("Left space => %d cols (penalty: %d); right space => %d cols (penalty: %d)\n",
cols_with_left_space, left_penalty,
cols_with_right_space, right_penalty);
if (last_space_cols && left_penalty <= right_penalty)
/* Prefer the left space. */
{
if (do_debug)
log_debug ("Breaking at left space.\n");
p = last_space;
}
else
{
if (do_debug)
log_debug ("Breaking at right space.\n");
}
if (! *p)
break;
*p = '\n';
p ++;
if (*p == ' ')
{
int spaces;
for (spaces = 1; p[spaces] == ' '; spaces ++)
;
memmove (p, &p[spaces], strlen (&p[spaces]) + 1);
}
line = p;
last_space = NULL;
last_space_cols = 0;
copied_last_space = 0;
}
}
/* Chop off any trailing space. */
while (text[strlen (text) - 1] == ' ')
text[strlen (text) - 1] = '\0';
/* If we inserted the trailing newline, then remove it. */
if (! copied_last_space && text[strlen (text) - 1] == '\n')
text[strlen (text) - 1] = '\0';
return text;
}

5
common/stringhelp.h
View File

@ -148,6 +148,11 @@ char **strsplit (char *string, char delim, char replacement, int *count);
/* Tokenize STRING using the set of delimiters in DELIM. */
char **strtokenize (const char *string, const char *delim);
/* Format a string so that it fits within about TARGET_COLS columns.
If IN_PLACE is 0, then TEXT is copied to a new buffer, which is
returned. Otherwise, TEXT is modified in place and returned.
Normally, target_cols will be 72 and max_cols is 80. */
char *format_text (char *text, int in_place, int target_cols, int max_cols);
/*-- mapstrings.c --*/
const char *map_static_macro_string (const char *string);

137
common/t-stringhelp.c
View File

@ -677,6 +677,142 @@ test_strtokenize (void)
}
}
static char *
stresc (char *s)
{
char *p;
int l = strlen (s) + 1;
for (p = s; *p; p ++)
if (*p == '\n')
l ++;
p = xmalloc (l);
for (l = 0; *s; s ++, l ++)
{
if (*s == ' ')
p[l] = '_';
else if (*p == '\n')
{
p[l ++] = '\\';
p[l ++] = 'n';
p[l] = '\n';
}
else
p[l] = *s;
}
p[l] = *s;
return p;
}
static void
test_format_text (void)
{
struct test
{
int target_cols, max_cols;
char *input;
char *expected;
};
struct test tests[] = {
{
10, 12,
"",
"",
},
{
10, 12,
" ",
"",
},
{
10, 12,
" ",
"",
},
{
10, 12,
" \n ",
" \n",
},
{
10, 12,
" \n \n ",
" \n \n",
},
{
10, 12,
"0123456789 0123456789 0",
"0123456789\n0123456789\n0",
},
{
10, 12,
" 0123456789 0123456789 0 ",
" 0123456789\n0123456789\n0",
},
{
10, 12,
"01 34 67 90 23 56 89 12 45 67 89 1",
"01 34 67\n90 23 56\n89 12 45\n67 89 1"
},
{
10, 12,
"01 34 67 90 23 56 89 12 45 67 89 1",
"01 34 67\n90 23 56\n89 12 45\n67 89 1"
},
{
72, 80,
"Warning: if you think you've seen more than 10 messages "
"signed by this key, then this key might be a forgery! "
"Carefully examine the email address for small variations "
"(e.g., additional white space). If the key is suspect, "
"then use 'gpg --tofu-policy bad \"FINGERPRINT\"' to mark it as being bad.\n",
"Warning: if you think you've seen more than 10 messages signed by this\n"
"key, then this key might be a forgery! Carefully examine the email\n"
"address for small variations (e.g., additional white space). If the key\n"
"is suspect, then use 'gpg --tofu-policy bad \"FINGERPRINT\"' to mark it as\n"
"being bad.\n"
},
{
72, 80,
"Normally, there is only a single key associated with an email "
"address. However, people sometimes generate a new key if "
"their key is too old or they think it might be compromised. "
"Alternatively, a new key may indicate a man-in-the-middle "
"attack! Before accepting this key, you should talk to or "
"call the person to make sure this new key is legitimate.",
"Normally, there is only a single key associated with an email "
"address.\nHowever, people sometimes generate a new key if "
"their key is too old or\nthey think it might be compromised. "
"Alternatively, a new key may indicate\na man-in-the-middle "
"attack! Before accepting this key, you should talk\nto or "
"call the person to make sure this new key is legitimate.",
}
};
int i;
int failed = 0;
for (i = 0; i < sizeof (tests) / sizeof (tests[0]); i ++)
{
struct test *test = &tests[i];
char *result =
format_text (test->input, 0, test->target_cols, test->max_cols);
if (strcmp (result, test->expected) != 0)
{
printf ("%s: Test #%d failed.\nExpected: '%s'\nResult: '%s'\n",
__func__, i + 1, stresc (test->expected), stresc (result));
failed ++;
}
xfree (result);
}
if (failed)
fail(0);
}
int
main (int argc, char **argv)
@ -692,6 +828,7 @@ main (int argc, char **argv)
test_make_absfilename_try ();
test_strsplit ();
test_strtokenize ();
test_format_text ();
xfree (home_buffer);
return 0;

16
g10/tofu.c
View File

@ -2038,7 +2038,9 @@ get_trust (struct dbs *dbs, const char *fingerprint, const char *email,
"Alternatively, a new key may indicate a man-in-the-middle "
"attack! Before accepting this key, you should talk to or "
"call the person to make sure this new key is legitimate.";
text = format_text (text, 0, 72, 80);
es_fprintf (fp, "\n%s\n", text);
xfree (text);
}
es_fputc ('\n', fp);
@ -2440,7 +2442,8 @@ show_statistics (struct dbs *dbs, const char *fingerprint,
if (policy == TOFU_POLICY_AUTO && messages < 10)
{
char *set_policy_command;
const char *text;
char *text;
char *tmp;
if (messages == 0)
log_info (_("Warning: we've have yet to see"
@ -2462,9 +2465,14 @@ show_statistics (struct dbs *dbs, const char *fingerprint,
"Carefully examine the email address for small variations "
"(e.g., additional white space). If the key is suspect, "
"then use '%s' to mark it as being bad.\n";
log_info (text,
messages, messages == 1 ? _("message") : _("message"),
set_policy_command);
tmp = xasprintf
(text,
messages, messages == 1 ? _("message") : _("message"),
set_policy_command);
text = format_text (tmp, 0, 72, 80);
xfree (tmp);
log_info ("%s", text);
xfree (text);
free (set_policy_command);
}
}