Files
pv/src/main/help.c
T

666 lines
20 KiB
C

/*
* Output command-line help to stdout.
*
* Copyright 2002-2008, 2010, 2012-2015, 2017, 2021, 2023-2026 Andrew Wood
*
* License GPLv3+: GNU GPL version 3 or later; see `docs/COPYING'.
*/
#include "config.h"
#include "pv.h"
#include <stdio.h>
#include <signal.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#if defined(ENABLE_NLS) && defined(HAVE_WCHAR_H)
#include <wchar.h>
#if defined(HAVE_WCTYPE_H)
#include <wctype.h>
#endif
#endif
/*
* Return the number of display columns needed to show the given
* null-terminated string.
*
* If NLS is disabled, or the string cannot be converted, this is just the
* same as "strlen()".
*/
static size_t display_width(const char *string)
{
size_t bytes;
if (NULL == string)
return 0;
bytes = strlen(string); /* flawfinder: ignore */
/*
* flawfinder rationale: it is explicitly required of the caller to
* provide a null-terminated string.
*/
return pv_strwidth(string, bytes);
}
/*
* The 7-bit ASCII version of display_word_wrap() below - does not
* understand multi-byte characters.
*/
static void display_word_wrap_7bit(const char *string, size_t display_width, size_t first_line_start,
size_t left_margin)
{
const char *start;
const char *end;
size_t wrap_at_width;
if (NULL == string)
return;
start = string;
wrap_at_width = display_width;
if (wrap_at_width > first_line_start)
wrap_at_width -= first_line_start;
/* Wrap lines that are too long. */
while (strlen(start) > wrap_at_width) { /* flawfinder: ignore */
/* flawfinder rationale: see above. */
/*
* Find the last space before the end of the display line,
* or if there isn't one, behave as if there was one at the
* end of the display line.
*/
end = start + wrap_at_width;
while ((end > start) && (end[0] != ' '))
end--;
if (end == start) {
end = start + wrap_at_width;
} else {
end++;
}
/* Display the string up to that space. */
printf("%.*s", (int) (end - start), start);
if (end == start)
end++;
start = end;
/*
* If there's more text left, start a new display line and
* pad it with spaces to the left margin, and change the
* wrap width to the display width minus the left margin.
*/
if (start[0] != '\0') {
printf("\n%*s", (int) left_margin, "");
if (display_width > left_margin) {
wrap_at_width = display_width - left_margin;
} else {
wrap_at_width = 1;
}
}
}
/* Display the remainder of the string. */
printf("%s", start);
}
/*
* Output a null-terminated string to standard output, word wrapping to
* "display_width" display character positions, assuming that the first line
* starts with the cursor already at "first_line_start" display character
* positions from the left, and left-padding any new lines after the first
* one with "left_margin" spaces.
*
* Wide characters are handled if NLS is enabled, but if they can't be, this
* falls back to a version which just counts bytes as characters.
*/
static void display_word_wrap(const char *string, size_t display_width, size_t first_line_start, size_t left_margin)
{
#if defined(ENABLE_NLS) && defined(HAVE_WCHAR_H)
size_t wrap_at_width;
size_t wide_char_count;
size_t wide_string_buffer_size;
wchar_t *wide_string;
size_t start_idx, chars_remaining;
debug("[%s], display_width=%d, first_line_start=%d, left_margin=%d", string, (int) display_width,
(int) first_line_start, (int) left_margin);
if (NULL == string)
return;
/* Calculate how many wide characters are in the multibyte string. */
/*@-nullpass@ */
/* splint note: see mbstowcs() call in pv_strwidth(). */
wide_char_count = mbstowcs(NULL, string, 0);
/*@+nullpass@ */
if (wide_char_count == (size_t) -1) {
debug("%s: %s: %s", "mbstowcs", string, strerror(errno));
display_word_wrap_7bit(string, display_width, first_line_start, left_margin);
return;
}
/*
* Allocate a buffer in which to convert the multibyte string to a
* wide-character string, plus one character for zero padding.
*/
wide_string_buffer_size = sizeof(*wide_string) * (1 + wide_char_count);
wide_string = malloc(wide_string_buffer_size);
if (NULL == wide_string) {
perror("malloc");
display_word_wrap_7bit(string, display_width, first_line_start, left_margin);
return;
}
memset(wide_string, 0, wide_string_buffer_size);
/* Convert the multibyte string to a wide-character string. */
if (mbstowcs(wide_string, string, 1 + wide_char_count) == (size_t) -1) {
debug("%s: %s: %s", "mbstowcs", string, strerror(errno));
free(wide_string);
display_word_wrap_7bit(string, display_width, first_line_start, left_margin);
return;
}
start_idx = 0;
wrap_at_width = display_width;
if (wrap_at_width > first_line_start)
wrap_at_width -= first_line_start;
chars_remaining = wide_char_count;
/* Wrap lines that are too long. */
/*@-unrecog@ *//* splint doesn't see the prototype for wcswidth(). */
while (chars_remaining > 0 && wcswidth(&(wide_string[start_idx]), chars_remaining) > (int) wrap_at_width) {
/*@+unrecog@ */
size_t next_idx, end_idx;
/*
* Find the last space before the end of the display line,
* or if there isn't one, behave as if there was one at the
* end of the display line.
*/
end_idx = start_idx + wrap_at_width;
while ((end_idx > start_idx) && (!iswspace(wide_string[end_idx])))
end_idx--;
if (end_idx == start_idx) {
end_idx = start_idx + wrap_at_width;
} else {
end_idx++;
}
next_idx = end_idx;
if (end_idx == start_idx)
next_idx++;
/* Display the string up to that space, a character at a time. */
while (start_idx < end_idx && start_idx < wide_char_count) {
char multi_byte_string[MB_CUR_MAX + 1]; /* flawfinder: ignore */
/*
* flawfinder rationale: the array is explicitly
* cleared, large enough according to the wctomb()
* manual, and the string is explicitly terminated.
*/
memset(multi_byte_string, 0, MB_CUR_MAX + 1);
if (wctomb(multi_byte_string, wide_string[start_idx]) >= 0) {
multi_byte_string[MB_CUR_MAX] = '\0';
printf("%s", multi_byte_string);
}
start_idx++;
}
start_idx = next_idx;
/*
* If there's more text left, start a new display line and
* pad it with spaces to the left margin, and change the
* wrap width to the display width minus the left margin.
*/
if (start_idx < wide_char_count) {
printf("\n%*s", (int) left_margin, "");
if (display_width > left_margin) {
wrap_at_width = display_width - left_margin;
} else {
wrap_at_width = 1;
}
chars_remaining = wide_char_count - start_idx;
} else {
/* Explicitly set to 0 to avoid underflow. */
chars_remaining = 0;
}
}
/* Display the remainder of the string, a character at a time. */
while (start_idx < wide_char_count) {
char multi_byte_string[MB_CUR_MAX + 1]; /* flawfinder: ignore */
/* flawfinder rationale as above. */
memset(multi_byte_string, 0, MB_CUR_MAX + 1);
if (wctomb(multi_byte_string, wide_string[start_idx]) >= 0) {
multi_byte_string[MB_CUR_MAX] = '\0';
printf("%s", multi_byte_string);
}
start_idx++;
}
free(wide_string);
#else /* ! defined(ENABLE_NLS) && defined(HAVE_WCHAR_H) */
display_word_wrap_7bit(string, display_width, first_line_start, left_margin);
#endif /* defined(ENABLE_NLS) && defined(HAVE_WCHAR_H) */
}
/*
* Structure holding the displayed descriptions of each option - the short
* option such as "-s", its long counterpart such as "--size", the name of
* its argument such as "SIZE", and the description of what the option does.
* Any of them may be NULL.
*
* In the initialiser for this structure, translatable strings are wrapped
* with N_() to indicate that they are to be translated into the operator's
* language by this function at run-time.
*
* Note that "opt_short" and "opt_long" should never be marked as
* translatable, as they must remain consistent across all locales.
*
* The list is terminated with a NULL opt_short value - to leave a gap, set
* opt_short to an empty string instead.
*/
struct option_definition_s {
/*@null@ */ const char *opt_short;
/*@null@ */ const char *opt_long;
/*@null@ *//*@observer@ */ const char *opt_argument;
/*@null@ *//*@observer@ */ const char *opt_description;
struct {
/*
* Structure holding the width, in display character
* positions, of the individual parts of the description of
* each option - calculated after initialisation, so that
* translation can be performed.
*/
size_t opt_short;
size_t opt_long;
size_t opt_argument;
size_t opt_description;
} width;
};
/*
* Display command-line help.
*/
void display_help(void)
{
struct option_definition_s option_definitions[] = {
{ "-p", "--progress", NULL,
N_("show progress bar"),
{ 0, 0, 0, 0} },
{ "-t", "--timer", NULL,
N_("show elapsed time"),
{ 0, 0, 0, 0} },
{ "-e", "--eta", NULL,
N_("show estimated time of arrival (completion)"),
{ 0, 0, 0, 0} },
{ "-I", "--fineta", NULL,
N_("show absolute estimated time of arrival (completion)"),
{ 0, 0, 0, 0} },
{ "-r", "--rate", NULL,
N_("show data transfer rate counter"),
{ 0, 0, 0, 0} },
{ "-a", "--average-rate", NULL,
N_("show data transfer average rate counter"),
{ 0, 0, 0, 0} },
{ "-b", "--bytes", NULL,
N_("show number of bytes transferred"),
{ 0, 0, 0, 0} },
{ "-T", "--buffer-percent", NULL,
N_("show percentage of transfer buffer in use"),
{ 0, 0, 0, 0} },
{ "-A", "--last-written", _("NUM"),
N_("show NUM bytes last written"),
{ 0, 0, 0, 0} },
{ "-F", "--format", N_("FORMAT"),
N_("set output format to FORMAT"),
{ 0, 0, 0, 0} },
{ "-n", "--numeric", NULL,
N_("output percentages, not visual information"),
{ 0, 0, 0, 0} },
{ "-q", "--quiet", NULL,
N_("do not output any transfer information at all"),
{ 0, 0, 0, 0} },
{ "", NULL, NULL, NULL, { 0, 0, 0, 0} },
{ "-8", "--bits", NULL,
N_("show number of bits transferred"),
{ 0, 0, 0, 0} },
{ "-k", "--si", NULL,
N_("treat suffixes as multiples of 1000 rather than 1024"),
{ 0, 0, 0, 0} },
{ "-W", "--wait", NULL,
N_("display nothing until first byte transferred"),
{ 0, 0, 0, 0} },
{ "-D", "--delay-start", N_("SEC"),
N_("display nothing until SEC seconds have passed"),
{ 0, 0, 0, 0} },
{ "-s", "--size", N_("SIZE"),
N_("set estimated data size to SIZE bytes"),
{ 0, 0, 0, 0} },
{ "-g", "--gauge", NULL,
N_("if size unknown, show rate vs max rate"),
{ 0, 0, 0, 0} },
{ "-l", "--line-mode", NULL,
N_("count lines instead of bytes"),
{ 0, 0, 0, 0} },
{ "-0", "--null", NULL,
N_("lines are null-terminated"),
{ 0, 0, 0, 0} },
{ "-i", "--interval", N_("SEC"),
N_("update every SEC seconds"),
{ 0, 0, 0, 0} },
{ "-m", "--average-rate-window", N_("SEC"),
N_("compute average rate over past SEC seconds (default 30s)"),
{ 0, 0, 0, 0} },
{ "-w", "--width", N_("WIDTH"),
N_("assume terminal is WIDTH characters wide"),
{ 0, 0, 0, 0} },
{ "-H", "--height", N_("HEIGHT"),
N_("assume terminal is HEIGHT rows high"),
{ 0, 0, 0, 0} },
{ "-N", "--name", N_("NAME"),
N_("prefix visual information with NAME"),
{ 0, 0, 0, 0} },
{ "-u", "--bar-style", N_("STYLE"),
N_("set default bar style to STYLE"),
{ 0, 0, 0, 0} },
{ "-x", "--extra-display", N_("SPEC"),
N_("also send progress to SPEC"),
{ 0, 0, 0, 0} },
{ "-9", "--conemu", NULL,
N_("set terminal progress state with OSC 9;4 (ConEmu)"),
{ 0, 0, 0, 0} },
{ "-v", "--stats", NULL,
N_("output transfer statistics at the end"),
{ 0, 0, 0, 0} },
{ "-f", "--force", NULL,
N_("output even if standard error is not a terminal"),
{ 0, 0, 0, 0} },
{ "-c", "--cursor", NULL,
N_("use cursor positioning escape sequences"),
{ 0, 0, 0, 0} },
{ "", NULL, NULL, NULL, { 0, 0, 0, 0} },
{ "-o", "--output", N_("FILE"),
N_("write output to FILE instead of stdout"),
{ 0, 0, 0, 0} },
{ "-L", "--rate-limit", N_("RATE"),
N_("limit transfer to RATE bytes per second"),
{ 0, 0, 0, 0} },
{ "-B", "--buffer-size", N_("BYTES"),
N_("use a buffer size of BYTES"),
{ 0, 0, 0, 0} },
{ "-C", "--no-splice", NULL,
N_("never use splice(), always use read/write"),
{ 0, 0, 0, 0} },
{ "-J", "--pipe-buffer-size", N_("BYTES"),
N_("set the pipe buffer size to BYTES"),
{ 0, 0, 0, 0} },
{ "-E", "--skip-errors", NULL,
N_("skip read errors in input"),
{ 0, 0, 0, 0} },
{ "-Z", "--error-skip-block", N_("BYTES"),
N_("skip errors in BYTES blocks at a time"),
{ 0, 0, 0, 0} },
{ "-S", "--stop-at-size", NULL,
N_("stop after --size bytes have been transferred"),
{ 0, 0, 0, 0} },
{ "-Y", "--sync", NULL,
N_("flush cache to disk after every write"),
{ 0, 0, 0, 0} },
{ "-K", "--direct-io", NULL,
N_("use direct I/O to bypass cache"),
{ 0, 0, 0, 0} },
{ "-O", "--sparse", NULL,
N_("try to seek instead of writing null bytes"),
{ 0, 0, 0, 0} },
{ "-X", "--discard", NULL,
N_("discard input instead of writing to output"),
{ 0, 0, 0, 0} },
{ "-U", "--store-and-forward", N_("FILE"),
N_("write all input to FILE before writing to output"),
{ 0, 0, 0, 0} },
{ "", NULL, NULL, NULL, { 0, 0, 0, 0} },
{ "-d", "--watchfd", N_("PID[:FD]|=NAME|@LISTFILE"),
N_("watch file FD opened by process PID"),
{ 0, 0, 0, 0} },
#ifdef PV_REMOTE_CONTROL
{ "-R", "--remote", N_("PID"),
N_("update settings of process PID"),
{ 0, 0, 0, 0} },
{ "-Q", "--query", N_("PID"),
N_("show progress of process PID"),
{ 0, 0, 0, 0} },
#endif /* PV_REMOTE_CONTROL */
{ "-M", "--monitor", "in|0|out|1|both|2",
N_("run a command and monitor its standard input, output, or both"),
{ 0, 0, 0, 0} },
{ "", NULL, NULL, NULL, { 0, 0, 0, 0} },
{ "-P", "--pidfile", N_("FILE"),
N_("save process ID in FILE"),
{ 0, 0, 0, 0} },
{ "-h", "--help", NULL,
N_("show this help and exit"),
{ 0, 0, 0, 0} },
{ "-V", "--version", NULL,
N_("show version information and exit"),
{ 0, 0, 0, 0} },
#ifdef ENABLE_DEBUGGING
{ "-!", "--debug", N_("FILE"),
N_("write debug logs to FILE"),
{ 0, 0, 0, 0} },
#endif
{ NULL, NULL, NULL, NULL, { 0, 0, 0, 0} }
};
unsigned int option_index;
size_t widest_option_width = 0;
size_t description_left_margin = 0;
size_t min_description_width = 50;
size_t right_margin = 77;
const char *program_description;
const char *bug_report_note;
char *format_sequences = NULL;
unsigned int terminal_width = 0, terminal_height = 0;
pv_screensize(&terminal_width, &terminal_height);
if (terminal_width > 5) {
right_margin = (size_t) (terminal_width - 3);
}
/*@-formatconst@ */
/*
* splint note: unavoidable use of %s in translated string. Should
* be hard to exploit - the message catalogue would have to be
* replaced or forced to load from another location.
*/
printf(_("Usage: %s [OPTION] [FILE]..."), PACKAGE_NAME);
/*@+formatconst@ */
printf("\n");
/*@-mustfreefresh@ */
/*
* splint note: the gettext calls made by _() cause memory leak
* warnings, but in this case it's unavoidable, and mitigated by the
* fact that each string is only translated once.
*/
program_description = _("Concatenate FILE(s), or standard input, to standard output, with monitoring.");
if (NULL != program_description) {
display_word_wrap(program_description, right_margin, 0, 0);
printf("\n");
}
printf("\n");
/*
* Translate the help text, and calculate the displayed width of
* each part of each option definition. The total display width of
* the short option, long option, and option argument together form
* the "option" width. The widest one is used to calculate the left
* margin for all of the descriptions to start at.
*/
for (option_index = 0; NULL != option_definitions[option_index].opt_short; option_index++) {
struct option_definition_s *definition;
size_t option_width;
definition = &(option_definitions[option_index]);
option_width = 0;
definition->width.opt_short = display_width(definition->opt_short);
definition->width.opt_long = 0;
definition->width.opt_argument = 0;
definition->width.opt_description = 0;
if (NULL != definition->opt_long) {
definition->width.opt_long = display_width(definition->opt_long);
}
if (NULL != definition->opt_argument) {
/*@observer@ */ const char *translated;
translated = _(definition->opt_argument);
if (NULL != translated) {
definition->opt_argument = translated;
}
definition->width.opt_argument = display_width(definition->opt_argument);
}
if (NULL != definition->opt_description) {
/*@observer@ */ const char *translated;
translated = _(definition->opt_description);
if (NULL != translated) {
definition->opt_description = translated;
}
definition->width.opt_description = display_width(definition->opt_description);
}
/*
* The option_width is padded with a left margin of 2
* spaces, a ", " between the short and long options, a
* space between the long option and the argument, and two
* spaces after the argument:
*
* " <short>, <long> <arg> <description>"
*
* If getopt_long() is unavailable then ", <long>" is
* omitted.
*/
option_width += 2 + definition->width.opt_short; /* " short" */
#ifdef HAVE_GETOPT_LONG
option_width += 2 + definition->width.opt_long; /* ", <long>" */
#endif
option_width += 1 + definition->width.opt_argument; /* " ARG" */
option_width += 2; /* final 2 spaces */
if (option_width > widest_option_width) {
widest_option_width = option_width;
}
}
/*
* Set the left margin for the option descriptions, based on the
* widest option width, or (right margin - min_description_width),
* whichever is less, so that there is always room for
* "min_description_width" characters of description. If there's
* not even room for that, set the left margin to 2.
*/
description_left_margin = 2;
if (right_margin > (min_description_width + 2))
description_left_margin = right_margin - min_description_width;
if (widest_option_width < description_left_margin) {
description_left_margin = widest_option_width;
}
debug("%s: description_left_margin=%d, widest_option_width=%d, right_margin=%d", "help display",
(int) description_left_margin, (int) widest_option_width, (int) right_margin);
/*
* Display each of the option definitions, word wrapping the
* descriptions.
*/
for (option_index = 0; NULL != option_definitions[option_index].opt_short; option_index++) {
struct option_definition_s *definition;
size_t option_width;
definition = &(option_definitions[option_index]);
option_width = 0;
if (definition->width.opt_short > 0 && NULL != definition->opt_short) {
printf(" %s", definition->opt_short);
option_width += 2 + definition->width.opt_short;
}
#ifdef HAVE_GETOPT_LONG
if (definition->width.opt_long > 0 && NULL != definition->opt_long) {
printf(", %s", definition->opt_long);
option_width += 2 + definition->width.opt_long;
}
#endif
if (definition->width.opt_argument > 0 && NULL != definition->opt_argument) {
printf(" %s", definition->opt_argument);
option_width += 1 + definition->width.opt_argument;
}
/* Just start a new line if there's no description. */
if ((0 == definition->width.opt_description) || (NULL == definition->opt_description)) {
printf("\n");
continue;
}
/*
* If the option (with 2 trailing spaces) is too wide, start
* a new line for the description. Either way, pad with
* spaces up to the description left margin.
*/
if ((option_width + 2) > description_left_margin) {
printf("\n%*s", (int) description_left_margin, "");
} else if (option_width < description_left_margin) {
printf("%*s", (int) (description_left_margin - option_width), "");
}
/* Output the description, word wrapped. */
display_word_wrap(definition->opt_description, right_margin, description_left_margin,
description_left_margin);
printf("\n");
}
format_sequences = pv_format_sequences();
if (NULL != format_sequences) {
const char *format_sequence_header;
format_sequence_header = _("Supported format sequences:");
if (NULL != format_sequence_header) {
printf("\n");
display_word_wrap(format_sequence_header, right_margin, 0, 0);
printf("\n");
}
printf("\n ");
display_word_wrap(format_sequences, right_margin, 2, 2);
free(format_sequences);
printf("\n");
}
printf("\n");
bug_report_note = _("Please report any bugs to: %s");
if (NULL != bug_report_note) {
/*@-formatconst@ */
/*
* splint note: see earlier "formatconst" note.
* flawfinder: same reason.
*/
printf(bug_report_note, PACKAGE_BUGREPORT); /* flawfinder: ignore */
/*@+formatconst@ */
}
printf("\n");
}