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authorDenys Vlasenko2018-01-22 14:38:51 +0100
committerDenys Vlasenko2018-01-22 14:38:51 +0100
commit8528d3d4f8240ab4715f671aa819fe034f0fc285 (patch)
tree4505944ecf37bb576d77cfa6681e02205ec22bec /miscutils/less.c
parente411cd071a2b6456c653f1a7179b83bef810bb72 (diff)
downloadbusybox-8528d3d4f8240ab4715f671aa819fe034f0fc285.zip
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less: optional support of -R
Based on patches by Lubomir Rintel <lkundrak@v3.sk> function old new delta read_lines 653 722 +69 less_main 2464 2531 +67 packed_usage 32202 32239 +37 ------------------------------------------------------------------------------ (add/remove: 0/0 grow/shrink: 3/0 up/down: 173/0) Total: 173 bytes Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Diffstat (limited to 'miscutils/less.c')
-rw-r--r--miscutils/less.c64
1 files changed, 63 insertions, 1 deletions
diff --git a/miscutils/less.c b/miscutils/less.c
index d60e6d9..c3221a4 100644
--- a/miscutils/less.c
+++ b/miscutils/less.c
@@ -99,6 +99,22 @@
//config: bool "Enable -N (dynamic switching of line numbers)"
//config: default y
//config: depends on FEATURE_LESS_DASHCMD
+//config:
+//config:config FEATURE_LESS_RAW
+//config: bool "Enable -R ('raw control characters')"
+//config: default y
+//config: depends on FEATURE_LESS_DASHCMD
+//config: help
+//config: This is essential for less applet to work with tools that use colors
+//config: and paging, such as git, systemd tools or nmcli.
+//config:
+//config:config FEATURE_LESS_ENV
+//config: bool "Take options from $LESS environment variable"
+//config: default y
+//config: depends on FEATURE_LESS_DASHCMD
+//config: help
+//config: This is essential for less applet to work with tools that use colors
+//config: and paging, such as git, systemd tools or nmcli.
//applet:IF_LESS(APPLET(less, BB_DIR_USR_BIN, BB_SUID_DROP))
@@ -106,7 +122,7 @@
//usage:#define less_trivial_usage
//usage: "[-E" IF_FEATURE_LESS_REGEXP("I")IF_FEATURE_LESS_FLAGS("Mm")
-//usage: "N" IF_FEATURE_LESS_TRUNCATE("S") "h~] [FILE]..."
+//usage: "N" IF_FEATURE_LESS_TRUNCATE("S") IF_FEATURE_LESS_TRUNCATE("R") "h~] [FILE]..."
//usage:#define less_full_usage "\n\n"
//usage: "View FILE (or stdin) one screenful at a time\n"
//usage: "\n -E Quit once the end of a file is reached"
@@ -121,6 +137,9 @@
//usage: IF_FEATURE_LESS_TRUNCATE(
//usage: "\n -S Truncate long lines"
//usage: )
+//usage: IF_FEATURE_LESS_RAW(
+//usage: "\n -R Remove color escape codes in input"
+//usage: )
//usage: "\n -~ Suppress ~s displayed past EOF"
#include <sched.h> /* sched_yield() */
@@ -157,6 +176,7 @@ enum {
FLAG_TILDE = 1 << 4,
FLAG_I = 1 << 5,
FLAG_S = (1 << 6) * ENABLE_FEATURE_LESS_TRUNCATE,
+ FLAG_R = (1 << 7) * ENABLE_FEATURE_LESS_RAW,
/* hijack command line options variable for internal state vars */
LESS_STATE_MATCH_BACKWARDS = 1 << 15,
};
@@ -207,6 +227,9 @@ struct globals {
regex_t pattern;
smallint pattern_valid;
#endif
+#if ENABLE_FEATURE_LESS_RAW
+ smallint in_escape;
+#endif
#if ENABLE_FEATURE_LESS_ASK_TERMINAL
smallint winsize_err;
#endif
@@ -513,6 +536,26 @@ static void read_lines(void)
*--p = '\0';
continue;
}
+#if ENABLE_FEATURE_LESS_RAW
+ if (option_mask32 & FLAG_R) {
+ if (c == '\033')
+ goto discard;
+ if (G.in_escape) {
+ if (isdigit(c)
+ || c == '['
+ || c == ';'
+ || c == 'm'
+ ) {
+ discard:
+ G.in_escape = (c != 'm');
+ readpos++;
+ continue;
+ }
+ /* Hmm, unexpected end of "ESC [ N ; N m" sequence */
+ G.in_escape = 0;
+ }
+ }
+#endif
{
size_t new_last_line_pos = last_line_pos + 1;
if (c == '\t') {
@@ -1776,6 +1819,25 @@ int less_main(int argc, char **argv)
num_files = argc - optind;
files = argv;
+ /* Tools typically pass LESS="FRSXMK".
+ * The options we don't understand are ignored. */
+ if (ENABLE_FEATURE_LESS_ENV) {
+ char *c = getenv("LESS");
+ if (c) while (*c) switch (*c++) {
+ case 'M':
+ option_mask32 |= FLAG_M;
+ break;
+ case 'R':
+ option_mask32 |= FLAG_R;
+ break;
+ case 'S':
+ option_mask32 |= FLAG_S;
+ break;
+ default:
+ break;
+ }
+ }
+
/* Another popular pager, most, detects when stdout
* is not a tty and turns into cat. This makes sense. */
if (!isatty(STDOUT_FILENO))