diff options
| -rw-r--r-- | toys/lsb/dmesg.c | 47 |
1 files changed, 30 insertions, 17 deletions
diff --git a/toys/lsb/dmesg.c b/toys/lsb/dmesg.c index 10032562..c8876757 100644 --- a/toys/lsb/dmesg.c +++ b/toys/lsb/dmesg.c @@ -4,19 +4,21 @@ * * http://refspecs.linuxfoundation.org/LSB_4.1.0/LSB-Core-generic/LSB-Core-generic/dmesg.html -USE_DMESG(NEWTOY(dmesg, "s#n#c", TOYFLAG_BIN)) +// We care that FLAG_c is 1, so keep c at the end. +USE_DMESG(NEWTOY(dmesg, "rs#<1n#c", TOYFLAG_BIN)) config DMESG bool "dmesg" default y help - usage: dmesg [-n level] [-s bufsize] | -c + usage: dmesg [-n LEVEL] [-s SIZE] | -c Print or control the kernel ring buffer. - -n Set kernel logging level (1-9). - -s Size of buffer to read (in bytes), default 16384. - -c Clear the ring buffer after printing. + -c Clear the ring buffer after printing + -n Set kernel logging LEVEL (1-9) + -r Raw output (with <level markers>) + -s Show the last SIZE many bytes */ #define FOR_dmesg @@ -31,25 +33,36 @@ GLOBALS( void dmesg_main(void) { // For -n just tell kernel to which messages to keep. - if (toys.optflags & 2) { - if (klogctl(8, NULL, TT.level)) error_exit("klogctl"); + if (toys.optflags & FLAG_n) { + if (klogctl(8, NULL, TT.level)) perror_exit("klogctl"); } else { - int size, i, last = '\n'; - char *data; + char *data, *to, *from; + int size; // Figure out how much data we need, and fetch it. size = TT.size; - if (size<2) size = 16384; - data = xmalloc(size); - size = klogctl(3 + (toys.optflags&1), data, size); + if (!size && 1>(size = klogctl(10, 0, 0))) perror_exit("klogctl");; + data = to = from = xmalloc(size+1); + size = klogctl(3 + (toys.optflags & FLAG_c), data, size); if (size < 0) error_exit("klogctl"); + data[size] = 0; - // Display data, filtering out level markers. - for (i=0; i<size; ) { - if (last=='\n' && data[i]=='<') i += 3; - else xputc(last = data[i++]); + // Filter out level markers. + if (!(toys.optflags & FLAG_r)) while ((from - data) < size) { + if ((from == data || from[-1] == '\n') && *from == '<') { + int i = stridx(from, '>'); + + if (i>0) from += i+1; + } + *(to++) = *(from++); + } else to = data+size; + + // Write result. The odds of somebody requesting a buffer of size 3 and + // getting "<1>" are remote, but don't segfault if they do. + if (to != data) { + xwrite(1, data, to-data); + if (to[-1] != '\n') xputc('\n'); } - if (last!='\n') xputc('\n'); if (CFG_TOYBOX_FREE) free(data); } } |