dmesg: allow specification of level range

include/strutils.h

@@ -211,7 +211,8 @@ extern int string_add_to_idarray(const char *list, int ary[],
 				 int (name2id)(const char *, size_t));
 
 extern int string_to_bitarray(const char *list, char *ary,
-			    int (*name2bit)(const char *, size_t));
+			    int (*name2bit)(const char *, size_t),
+			    size_t allow_range);
 
 extern int string_to_bitmask(const char *list,
 			     unsigned long *mask,

lib/strutils.c

@@ -724,11 +724,16 @@ int string_add_to_idarray(const char *list, int ary[], size_t arysz,
  * as a position in the 'ary' bit array. It means that the 'id' has to be in
  * range <0..N> where N < sizeof(ary) * NBBY.
  *
+ * If allow_range is enabled:
+ * An item ending in '+' also sets all bits in <0..N>.
+ * An item beginning with '+' also sets all bits in <N..allow_minus>.
+ *
  * Returns: 0 on success, <0 on error.
  */
 int string_to_bitarray(const char *list,
 		     char *ary,
-		     int (*name2bit)(const char *, size_t))
+		     int (*name2bit)(const char *, size_t),
+		     size_t allow_range)
 {
 	const char *begin = NULL, *p;
 
@@ -737,7 +742,7 @@ int string_to_bitarray(const char *list,
 
 	for (p = list; p && *p; p++) {
 		const char *end = NULL;
-		int bit;
+		int bit, set_lower = 0, set_higher = 0;
 
 		if (!begin)
 			begin = p;		/* begin of the level name */
@@ -749,11 +754,26 @@ int string_to_bitarray(const char *list,
 			continue;
 		if (end <= begin)
 			return -1;
+		if (allow_range) {
+			if (*(end - 1) == '+') {
+				end--;
+				set_lower = 1;
+			} else if (*begin == '+') {
+				begin++;
+				set_higher = 1;
+			}
+		}
 
 		bit = name2bit(begin, end - begin);
 		if (bit < 0)
 			return bit;
 		setbit(ary, bit);
+		if (set_lower)
+			while (--bit >= 0)
+				setbit(ary, bit);
+		else if (set_higher)
+			while (++bit < (int) allow_range)
+				setbit(ary, bit);
 		begin = NULL;
 		if (end && !*end)
 			break;

sys-utils/dmesg.1.adoc

@@ -84,6 +84,14 @@ Restrict output to the given (comma-separated) _list_ of levels. For example:
 *dmesg --level=err,warn*
 +
 will print error and warning messages only. For all supported levels see the *--help* output.
++
+Appending a plus *+* to a level name also includes all higher levels. For example:
++
+*dmesg --level=err+*
++
+will print levels *err*, *crit*, *alert* and *emerg*.
++
+Prepending it will include all lower levels.
 
 *-n*, *--console-level* _level_::
 Set the _level_ at which printing of messages is done to the console. The _level_ is a level number or abbreviation of the level name. For all supported levels see the *--help* output.

sys-utils/dmesg.c

@@ -1475,7 +1475,7 @@ int main(int argc, char *argv[])
 		case 'f':
 			ctl.fltr_fac = 1;
 			if (string_to_bitarray(optarg,
-					     ctl.facilities, parse_facility) < 0)
+					     ctl.facilities, parse_facility, 0) < 0)
 				return EXIT_FAILURE;
 			break;
 		case 'H':
@@ -1499,7 +1499,8 @@ int main(int argc, char *argv[])
 		case 'l':
 			ctl.fltr_lev= 1;
 			if (string_to_bitarray(optarg,
-					     ctl.levels, parse_level) < 0)
+					     ctl.levels, parse_level,
+					     ARRAY_SIZE(level_names)) < 0)
 				return EXIT_FAILURE;
 			break;
 		case 'n':

tests/expected/dmesg/console-levels

@@ -102,3 +102,147 @@
 [658503.000000] example[87]
 [857375.000000] example[95]
 [1092727.000000] example[103]
+[    0.000000] example[0]
+[    1.000000] example[1]
+[    8.000000] example[2]
+[   27.000000] example[3]
+[  512.000000] example[8]
+[  729.000000] example[9]
+[ 1000.000000] example[10]
+[ 1331.000000] example[11]
+[ 4096.000000] example[16]
+[ 4913.000000] example[17]
+[ 5832.000000] example[18]
+[ 6859.000000] example[19]
+[13824.000000] example[24]
+[15625.000000] example[25]
+[17576.000000] example[26]
+[19683.000000] example[27]
+[32768.000000] example[32]
+[35937.000000] example[33]
+[39304.000000] example[34]
+[42875.000000] example[35]
+[64000.000000] example[40]
+[68921.000000] example[41]
+[74088.000000] example[42]
+[79507.000000] example[43]
+[110592.000000] example[48]
+[117649.000000] example[49]
+[125000.000000] example[50]
+[132651.000000] example[51]
+[175616.000000] example[56]
+[185193.000000] example[57]
+[195112.000000] example[58]
+[205379.000000] example[59]
+[262144.000000] example[64]
+[274625.000000] example[65]
+[287496.000000] example[66]
+[300763.000000] example[67]
+[373248.000000] example[72]
+[389017.000000] example[73]
+[405224.000000] example[74]
+[421875.000000] example[75]
+[512000.000000] example[80]
+[531441.000000] example[81]
+[551368.000000] example[82]
+[571787.000000] example[83]
+[681472.000000] example[88]
+[704969.000000] example[89]
+[729000.000000] example[90]
+[753571.000000] example[91]
+[884736.000000] example[96]
+[912673.000000] example[97]
+[941192.000000] example[98]
+[970299.000000] example[99]
+[    0.000000] example[0]
+[  512.000000] example[8]
+[ 4096.000000] example[16]
+[13824.000000] example[24]
+[32768.000000] example[32]
+[64000.000000] example[40]
+[110592.000000] example[48]
+[175616.000000] example[56]
+[262144.000000] example[64]
+[373248.000000] example[72]
+[512000.000000] example[80]
+[681472.000000] example[88]
+[884736.000000] example[96]
+[   27.000000] example[3]
+[   64.000000] example[4]
+[  125.000000] example[5]
+[  216.000000] example[6]
+[  343.000000] example[7]
+[ 1331.000000] example[11]
+[ 1728.000000] example[12]
+[ 2197.000000] example[13]
+[ 2744.000000] example[14]
+[ 3375.000000] example[15]
+[ 6859.000000] example[19]
+[ 8000.000000] example[20]
+[ 9261.000000] example[21]
+[10648.000000] example[22]
+[12167.000000] example[23]
+[19683.000000] example[27]
+[21952.000000] example[28]
+[24389.000000] example[29]
+[27000.000000] example[30]
+[29791.000000] example[31]
+[42875.000000] example[35]
+[46656.000000] example[36]
+[50653.000000] example[37]
+[54872.000000] example[38]
+[59319.000000] example[39]
+[79507.000000] example[43]
+[85184.000000] example[44]
+[91125.000000] example[45]
+[97336.000000] example[46]
+[103823.000000] example[47]
+[132651.000000] example[51]
+[140608.000000] example[52]
+[148877.000000] example[53]
+[157464.000000] example[54]
+[166375.000000] example[55]
+[205379.000000] example[59]
+[216000.000000] example[60]
+[226981.000000] example[61]
+[238328.000000] example[62]
+[250047.000000] example[63]
+[300763.000000] example[67]
+[314432.000000] example[68]
+[328509.000000] example[69]
+[343000.000000] example[70]
+[357911.000000] example[71]
+[421875.000000] example[75]
+[438976.000000] example[76]
+[456533.000000] example[77]
+[474552.000000] example[78]
+[493039.000000] example[79]
+[571787.000000] example[83]
+[592704.000000] example[84]
+[614125.000000] example[85]
+[636056.000000] example[86]
+[658503.000000] example[87]
+[753571.000000] example[91]
+[778688.000000] example[92]
+[804357.000000] example[93]
+[830584.000000] example[94]
+[857375.000000] example[95]
+[970299.000000] example[99]
+[1000000.000000] example[100]
+[1030301.000000] example[101]
+[1061208.000000] example[102]
+[1092727.000000] example[103]
+[  343.000000] example[7]
+[ 3375.000000] example[15]
+[12167.000000] example[23]
+[29791.000000] example[31]
+[59319.000000] example[39]
+[103823.000000] example[47]
+[166375.000000] example[55]
+[250047.000000] example[63]
+[357911.000000] example[71]
+[493039.000000] example[79]
+[658503.000000] example[87]
+[857375.000000] example[95]
+[1092727.000000] example[103]
+test_dmesg: unknown level '+'

tests/ts/dmesg/console-levels

@@ -27,4 +27,10 @@ for I in {-1..8}; do
 	$TS_HELPER_DMESG -F $TS_SELF/input -l $I >> $TS_OUTPUT 2>/dev/null
 done
 
+$TS_HELPER_DMESG -F $TS_SELF/input -l err+ >> $TS_OUTPUT 2>/dev/null
+$TS_HELPER_DMESG -F $TS_SELF/input -l emerg+ >> $TS_OUTPUT 2>/dev/null
+$TS_HELPER_DMESG -F $TS_SELF/input -l +err >> $TS_OUTPUT 2>/dev/null
+$TS_HELPER_DMESG -F $TS_SELF/input -l +debug >> $TS_OUTPUT 2>/dev/null
+$TS_HELPER_DMESG -F $TS_SELF/input -l + 2>> $TS_OUTPUT >/dev/null
+
 ts_finalize