man: allow nroff and tbl commands be overridden; unmangle writing to files

Parse this in config files:
	 DEFINE col ...
	 DEFINE tbl ...
	 DEFINE nroff ...
Add width options to nroff command line.
Use "tbl", not "gtbl", as default tbl command.
Export GROFF_NO_SGR=1 and use "col -b -p -x" instead of pager when writing to file.

function                                             old     new   delta
man_main                                             735     863    +128
if_redefined                                           -      64     +64
show_manpage                                         199     169     -30
------------------------------------------------------------------------------
(add/remove: 1/0 grow/shrink: 1/1 up/down: 192/-30)           Total: 162 bytes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
This commit is contained in:
Denys Vlasenko 2016-10-30 22:31:30 +01:00
parent d4f3db9427
commit a92a74961d

View File

@ -11,6 +11,7 @@
//usage: "\n -w Show page locations"
#include "libbb.h"
#include "common_bufsiz.h"
enum {
OPT_a = 1, /* all */
@ -18,7 +19,6 @@ enum {
};
/* This is what I see on my desktop system being executed:
(
echo ".ll 12.4i"
echo ".nr LL 12.4i"
@ -28,11 +28,39 @@ echo ".\\\""
echo ".pl \n(nlu+10"
) | gtbl | nroff -Tlatin1 -mandoc | less
On another system I see this:
... | tbl | nroff -mandoc -rLL=<NNN>n -rLT=<NNN>n -Tutf8 | less
where <NNN> is screen width minus 5.
Replacing "DEFINE nroff nroff -mandoc" in /etc/man_db.conf
changes "nroff -mandoc" part; -rLL=<NNN>n, -rLT=<NNN>n and -Tutf8 parts are
appended to the user-specified command.
Redirecting to a pipe or file sets GROFF_NO_SGR=1 to prevent color escapes,
and uses "col -b -p -x" instead of pager, this filters out backspace
and underscore tricks.
*/
static int show_manpage(const char *pager, char *man_filename, int man, int level);
struct globals {
const char *col;
const char *tbl;
const char *nroff;
const char *pager;
} FIX_ALIASING;
#define G (*(struct globals*)bb_common_bufsiz1)
#define INIT_G() do { \
setup_common_bufsiz(); \
G.col = "col"; \
G.tbl = "tbl"; \
/* replaced -Tlatin1 with -Tascii for non-UTF8 displays */; \
G.nroff = "nroff -mandoc -Tascii"; \
G.pager = ENABLE_LESS ? "less" : "more"; \
} while (0)
static int run_pipe(const char *pager, char *man_filename, int man, int level)
static int show_manpage(char *man_filename, int man, int level);
static int run_pipe(char *man_filename, int man, int level)
{
char *cmd;
@ -95,7 +123,7 @@ static int run_pipe(const char *pager, char *man_filename, int man, int level)
man_filename = xasprintf("%s/%s", man_filename, linkname);
free(line);
/* Note: we leak "new" man_filename string as well... */
if (show_manpage(pager, man_filename, man, level + 1))
if (show_manpage(man_filename, man, level + 1))
return 1;
/* else: show the link, it's better than nothing */
}
@ -103,20 +131,29 @@ static int run_pipe(const char *pager, char *man_filename, int man, int level)
ordinary_manpage:
close(STDIN_FILENO);
open_zipped(man_filename, /*fail_if_not_compressed:*/ 0); /* guaranteed to use fd 0 (STDIN_FILENO) */
if (man) {
/* "man man" formats to screen width.
* "man man >file" formats to default 80 columns.
* "man man | cat" formats to default 80 columns.
*/
int w = get_terminal_width(STDOUT_FILENO);
if (w > 10)
w -= 2;
/* "2>&1" is added so that nroff errors are shown in pager too.
* Otherwise it may show just empty screen */
cmd = xasprintf(
/* replaced -Tlatin1 with -Tascii for non-UTF8 displays */
man ? "gtbl | nroff -Tascii -mandoc 2>&1 | %s"
: "%s",
pager);
cmd = xasprintf("%s | %s -rLL=%un -rLT=%un 2>&1 | %s",
G.tbl, G.nroff, w, w,
G.pager);
} else {
cmd = xstrdup(G.pager);
}
system(cmd);
free(cmd);
return 1;
}
/* man_filename is of the form "/dir/dir/dir/name.s" */
static int show_manpage(const char *pager, char *man_filename, int man, int level)
static int show_manpage(char *man_filename, int man, int level)
{
#if SEAMLESS_COMPRESSION
/* We leak this allocation... */
@ -125,26 +162,26 @@ static int show_manpage(const char *pager, char *man_filename, int man, int leve
#endif
#if ENABLE_FEATURE_SEAMLESS_LZMA
if (run_pipe(pager, filename_with_zext, man, level))
if (run_pipe(filename_with_zext, man, level))
return 1;
#endif
#if ENABLE_FEATURE_SEAMLESS_XZ
strcpy(ext, "xz");
if (run_pipe(pager, filename_with_zext, man, level))
if (run_pipe(filename_with_zext, man, level))
return 1;
#endif
#if ENABLE_FEATURE_SEAMLESS_BZ2
strcpy(ext, "bz2");
if (run_pipe(pager, filename_with_zext, man, level))
if (run_pipe(filename_with_zext, man, level))
return 1;
#endif
#if ENABLE_FEATURE_SEAMLESS_GZ
strcpy(ext, "gz");
if (run_pipe(pager, filename_with_zext, man, level))
if (run_pipe(filename_with_zext, man, level))
return 1;
#endif
return run_pipe(pager, man_filename, man, level);
return run_pipe(man_filename, man, level);
}
static char **add_MANPATH(char **man_path_list, int *count_mp, char *path)
@ -182,11 +219,20 @@ static char **add_MANPATH(char **man_path_list, int *count_mp, char *path)
return man_path_list;
}
static const char *if_redefined(const char *var, const char *key, const char *line)
{
if (!is_prefixed_with(line, key))
return var;
line += strlen(key);
if (!isspace(line[0]))
return var;
return xstrdup(skip_whitespace(line));
}
int man_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int man_main(int argc UNUSED_PARAM, char **argv)
{
parser_t *parser;
const char *pager = ENABLE_LESS ? "less" : "more";
char *sec_list;
char *cur_path, *cur_sect;
char **man_path_list;
@ -195,6 +241,8 @@ int man_main(int argc UNUSED_PARAM, char **argv)
int opt, not_found;
char *token[2];
INIT_G();
opt_complementary = "-1"; /* at least one argument */
opt = getopt32(argv, "+aw");
argv += optind;
@ -228,9 +276,10 @@ int man_main(int argc UNUSED_PARAM, char **argv)
if (!token[1])
continue;
if (strcmp("DEFINE", token[0]) == 0) {
if (is_prefixed_with(token[1], "pager")) {
pager = xstrdup(skip_whitespace(token[1] + 5));
}
G.col = if_redefined(G.tbl , "col", token[1]);
G.tbl = if_redefined(G.tbl , "tbl", token[1]);
G.nroff = if_redefined(G.nroff, "nroff", token[1]);
G.pager = if_redefined(G.pager, "pager", token[1]);
} else
if (strcmp("MANDATORY_MANPATH"+10, token[0]) == 0 /* "MANPATH"? */
|| strcmp("MANDATORY_MANPATH", token[0]) == 0
@ -250,7 +299,12 @@ int man_main(int argc UNUSED_PARAM, char **argv)
if (!env_pager)
env_pager = getenv("PAGER");
if (env_pager)
pager = env_pager;
G.pager = env_pager;
}
if (!isatty(STDOUT_FILENO)) {
putenv((char*)"GROFF_NO_SGR=1");
G.pager = xasprintf("%s -b -p -x", G.col);
}
not_found = 0;
@ -259,7 +313,7 @@ int man_main(int argc UNUSED_PARAM, char **argv)
cur_mp = 0;
if (strchr(*argv, '/')) {
found = show_manpage(pager, *argv, /*man:*/ 1, 0);
found = show_manpage(*argv, /*man:*/ 1, 0);
goto check_found;
}
while ((cur_path = man_path_list[cur_mp++]) != NULL) {
@ -280,7 +334,7 @@ int man_main(int argc UNUSED_PARAM, char **argv)
sect_len, cur_sect,
*argv,
sect_len, cur_sect);
found_here = show_manpage(pager, man_filename, cat0man1, 0);
found_here = show_manpage(man_filename, cat0man1, 0);
found |= found_here;
cat0man1 += found_here + 1;
free(man_filename);