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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-06 01:46:30 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-06 01:46:30 +0000 |
commit | b5896ba9f6047e7031e2bdee0622d543e11a6734 (patch) | |
tree | fd7b460593a2fee1be579bec5697e6d887ea3421 /src/util/line_wrap.c | |
parent | Initial commit. (diff) | |
download | postfix-b5896ba9f6047e7031e2bdee0622d543e11a6734.tar.xz postfix-b5896ba9f6047e7031e2bdee0622d543e11a6734.zip |
Adding upstream version 3.4.23.upstream/3.4.23upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/util/line_wrap.c')
-rw-r--r-- | src/util/line_wrap.c | 122 |
1 files changed, 122 insertions, 0 deletions
diff --git a/src/util/line_wrap.c b/src/util/line_wrap.c new file mode 100644 index 0000000..0f399e8 --- /dev/null +++ b/src/util/line_wrap.c @@ -0,0 +1,122 @@ +/*++ +/* NAME +/* line_wrap 3 +/* SUMMARY +/* wrap long lines upon output +/* SYNOPSIS +/* #include <line_wrap.h> +/* +/* void line_wrap(string, len, indent, output_fn, context) +/* const char *buf; +/* int len; +/* int indent; +/* void (*output_fn)(const char *str, int len, int indent, void *context); +/* void *context; +/* DESCRIPTION +/* The \fBline_wrap\fR routine outputs the specified string via +/* the specified output function, and attempts to keep output lines +/* shorter than the specified length. The routine does not attempt to +/* break long words that do not fit on a single line. Upon output, +/* trailing whitespace is stripped. +/* +/* Arguments +/* .IP string +/* The input, which cannot contain any newline characters. +/* .IP len +/* The desired maximal output line length. +/* .IP indent +/* The desired amount of indentation of the second etc. output lines +/* with respect to the first output line. A negative indent causes +/* only the first line to be indented; a positive indent causes all +/* but the first line to be indented. A zero count causes no indentation. +/* .IP output_fn +/* The output function that is called with as arguments a string +/* pointer, a string length, a non-negative indentation count, and +/* application context. A typical implementation looks like this: +/* .sp +/* .nf +/* .na +void print(const char *str, int len, int indent, void *context) +{ + VSTREAM *fp = (VSTREAM *) context; + + vstream_fprintf(fp, "%*s%.*s", indent, "", len, str); +} +/* .fi +/* .ad +/* .IP context +/* Application context that is passed on to the output function. +/* For example, a VSTREAM pointer, or a structure that contains +/* a VSTREAM pointer. +/* BUGS +/* No tab expansion and no backspace processing. +/* LICENSE +/* .ad +/* .fi +/* The Secure Mailer license must be distributed with this software. +/* AUTHOR(S) +/* Wietse Venema +/* IBM T.J. Watson Research +/* P.O. Box 704 +/* Yorktown Heights, NY 10598, USA +/*--*/ + +/* System library. */ + +#include <sys_defs.h> +#include <string.h> +#include <ctype.h> + +/* Utility library. */ + +#include <line_wrap.h> + +/* line_wrap - wrap long lines upon output */ + +void line_wrap(const char *str, int len, int indent, LINE_WRAP_FN output_fn, + void *context) +{ + const char *start_line; + const char *word; + const char *next_word; + const char *next_space; + int line_len; + int curr_len; + int curr_indent; + + if (indent < 0) { + curr_indent = -indent; + curr_len = len + indent; + } else { + curr_indent = 0; + curr_len = len; + } + + /* + * At strategic positions, output what we have seen, after stripping off + * trailing blanks. + */ + for (start_line = word = str; word != 0; word = next_word) { + next_space = word + strcspn(word, " \t"); + if (word > start_line) { + if (next_space - start_line > curr_len) { + line_len = word - start_line; + while (line_len > 0 && ISSPACE(start_line[line_len - 1])) + line_len--; + output_fn(start_line, line_len, curr_indent, context); + while (*word && ISSPACE(*word)) + word++; + if (start_line == str) { + curr_indent += indent; + curr_len -= indent; + } + start_line = word; + } + } + next_word = *next_space ? next_space + 1 : 0; + } + line_len = strlen(start_line); + while (line_len > 0 && ISSPACE(start_line[line_len - 1])) + line_len--; + output_fn(start_line, line_len, curr_indent, context); +} |