← Commit list

a92a74961

Denys Vlasenko

2016-10-30

SUCCESS Duration: 277s

Subject

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

Binary

No binary (build failed)

Architecture & Compiler Flags

Architecture: x86_64-linux-gnu Compiler: gcc (Ubuntu 11.4.0-1ubuntu1~22.04.3) 11.4.0

—

Build Log

(log yok)

Commit Diff GitHub →

miscutils/man.c +79 -25

miscutils/man.c+79 -25

@@ -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:

-	static int show_manpage(const char pager, char man_filename, int man, int level);
+	... \| tbl \| nroff -mandoc -rLL=<NNN>n -rLT=<NNN>n -Tutf8 \| less

-	static int run_pipe(const char pager, char man_filename, int man, int level)
+	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.
+	*/
+
+	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 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) */
-	/* "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);
+	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("%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);