[LEDE-DEV] [PATCH ubox v2] logread: Add support for output template
Philip Prindeville
philipp_subx at redfish-solutions.com
Mon May 1 10:48:42 PDT 2017
Inline…
> On Apr 27, 2017, at 5:33 PM, Henry Chang <mr.changyuheng at gmail.com> wrote:
>
> From: Henry Chang <mr.changyuheng at gmail.com>
>
> Signed-off-by: Henry Chang <mr.changyuheng at gmail.com>
> ---
> log/logread.c | 153 ++++++++++++++++++++++++++++++++++++++++++++++++----------
> 1 file changed, 127 insertions(+), 26 deletions(-)
>
> diff --git a/log/logread.c b/log/logread.c
> index edac1d9..3e3406a 100644
> --- a/log/logread.c
> +++ b/log/logread.c
> @@ -56,10 +56,25 @@ static const struct blobmsg_policy log_policy[] = {
> [LOG_TIME] = { .name = "time", .type = BLOBMSG_TYPE_INT64 },
> };
>
> +enum {
> + TPL_FIELD_MESSAGE,
> + TPL_FIELD_PRIORITY,
> + TPL_FIELD_SOURCE,
> + TPL_FIELD_TIMESTAMP,
> +};
> +
> +static const char *TPL_FIELDS[] = {
> + [TPL_FIELD_MESSAGE] = "%message%",
> + [TPL_FIELD_PRIORITY] = "%priority%",
> + [TPL_FIELD_SOURCE] = "%source%",
> + [TPL_FIELD_TIMESTAMP] = "%timestamp%",
> +};
> +
> static struct uloop_timeout retry;
> static struct uloop_fd sender;
> static regex_t regexp_preg;
> static const char *log_file, *log_ip, *log_port, *log_prefix, *pid_file, *hostname, *regexp_pattern;
> +static const char *log_template;
> static int log_type = LOG_STDOUT;
> static int log_size, log_udp, log_follow, log_trailer_null = 0;
> static int log_timestamp;
> @@ -102,6 +117,7 @@ static int log_notify(struct blob_attr *msg)
> struct stat s;
> char buf[512];
> char buf_ts[32];
> + char buf_p[32];
> uint32_t p;
> char *str;
> time_t t;
> @@ -137,34 +153,108 @@ static int log_notify(struct blob_attr *msg)
> regexec(®exp_preg, m, 0, NULL, 0) == REG_NOMATCH)
> return 0;
> t = blobmsg_get_u64(tb[LOG_TIME]) / 1000;
> - if (log_timestamp) {
> - t_ms = blobmsg_get_u64(tb[LOG_TIME]) % 1000;
> - snprintf(buf_ts, sizeof(buf_ts), "[%lu.%03u] ",
> - (unsigned long)t, t_ms);
> - }
> + t_ms = blobmsg_get_u64(tb[LOG_TIME]) % 1000;
> + snprintf(buf_ts, sizeof(buf_ts), "[%lu.%03u] ", (unsigned long) t, t_ms);
> c = ctime(&t);
> p = blobmsg_get_u32(tb[LOG_PRIO]);
> c[strlen(c) - 1] = '\0';
> str = blobmsg_format_json(msg, true);
> + snprintf(buf_p, sizeof buf_p, "%u", p);
Even on an 64BIT architecture, an unsigned will be 32-bits and therefore 10 decimal digits plus NUL… not sure why buf_p[] needs to be so large.
> +
> + if (log_template) {
> + char buf2[512];
> + size_t len;
> + int tpli = -1;
> +
> + if ((len = strlen(log_template) + 1) > sizeof buf) {
> + fprintf(stderr, "template is larger than the internal buffer\n");
> + return 1;
> + }
> + strncpy(buf, log_template, len);
> +
> + char *substr = buf;
> + for (;;) {
> + char *substrnext = NULL;
> + for (int i = 0; i < sizeof TPL_FIELDS / sizeof (char *); ++i) {
If ‘i’ is always a positive value, why not make it unsigned?
> + char *substrbuf = strstr(substr, TPL_FIELDS[i]);
> + if (!substrbuf)
> + continue;
> + if (!substrnext || substrbuf < substrnext) {
> + substrnext = substrbuf;
> + tpli = i;
> + }
> + }
> + substr = substrnext;
> + if (!substr)
> + break;
> + char *field = NULL;
> + switch (tpli) {
The rest of this file matches switch/case indent… please go with that.
> + case TPL_FIELD_MESSAGE:
> + field = m;
> + break;
> + case TPL_FIELD_PRIORITY:
> + field = buf_p;
> + break;
> + case TPL_FIELD_SOURCE:
> + switch (blobmsg_get_u32(tb[LOG_SOURCE])) {
> + case SOURCE_KLOG:
> + field = "kernel";
> + break;
> + case SOURCE_SYSLOG:
> + field = "syslog";
> + break;
> + case SOURCE_INTERNAL:
> + field = "internal";
> + break;
> + default:
> + field = "-“;
Please use a ‘break’ even on the last case of a ‘switch’.
> + }
> + case TPL_FIELD_TIMESTAMP:
> + field = buf_ts;
> + break;
> + }
> + if (!field || tpli < 0)
> + continue;
> + *buf2 = '\0';
> + size_t fieldlen = strlen(field);
> + strncat(buf2, buf, substr - buf);
> + if (strlen(buf2) + fieldlen + 1 > sizeof buf2) {
I would take the strlen() and assign it to a variable. This makes debugging simpler.
> + fprintf(stderr, "template is larger than the internal buffer\n");
> + return 1;
> + }
> + strncat(buf2, field, fieldlen);
> + len = strlen(TPL_FIELDS[tpli]);
> + if (strlen(buf2) + strlen(substr) - len + 1 > sizeof buf2) {
Ditto.
> + fprintf(stderr, "template is larger than the internal buffer\n");
> + return 1;
> + }
> + strncat(buf2, substr + len, strlen(substr) - len);
strlen() isn’t cheap. Please don’t call it multiple times. Save it into a variable and use that.
> + strncpy(buf, buf2, strlen(buf2) + 1);
> + substr += fieldlen;
> + }
> + }
> +
> if (log_type == LOG_NET) {
> int err;
>
> - snprintf(buf, sizeof(buf), "<%u>", p);
> - strncat(buf, c + 4, 16);
> - if (log_timestamp) {
> - strncat(buf, buf_ts, sizeof(buf) - strlen(buf) - 1);
> + if (!log_template) {
> + snprintf(buf, sizeof(buf), "<%u>", p);
> + strncat(buf, c + 4, 16);
Please avoid magic numbers, even if they were in the original code.
> + if (log_timestamp) {
> + strncat(buf, buf_ts, sizeof(buf) - strlen(buf) - 1);
> + }
> + if (hostname) {
> + strncat(buf, hostname, sizeof(buf) - strlen(buf) - 1);
> + strncat(buf, " ", sizeof(buf) - strlen(buf) - 1);
> + }
> + if (log_prefix) {
> + strncat(buf, log_prefix, sizeof(buf) - strlen(buf) - 1);
> + strncat(buf, ": ", sizeof(buf) - strlen(buf) - 1);
> + }
> + if (blobmsg_get_u32(tb[LOG_SOURCE]) == SOURCE_KLOG)
> + strncat(buf, "kernel: ", sizeof(buf) - strlen(buf) - 1);
> + strncat(buf, m, sizeof(buf) - strlen(buf) - 1);
I’m looking at all these strncat()’s and thinking that you’d be better off using fmemopen() instead. Less chance of overrunning a buffer since all of that is taken care of for you.
> }
> - if (hostname) {
> - strncat(buf, hostname, sizeof(buf) - strlen(buf) - 1);
> - strncat(buf, " ", sizeof(buf) - strlen(buf) - 1);
> - }
> - if (log_prefix) {
> - strncat(buf, log_prefix, sizeof(buf) - strlen(buf) - 1);
> - strncat(buf, ": ", sizeof(buf) - strlen(buf) - 1);
> - }
> - if (blobmsg_get_u32(tb[LOG_SOURCE]) == SOURCE_KLOG)
> - strncat(buf, "kernel: ", sizeof(buf) - strlen(buf) - 1);
> - strncat(buf, m, sizeof(buf) - strlen(buf) - 1);
> if (log_udp)
> err = write(sender.fd, buf, strlen(buf));
> else {
> @@ -183,11 +273,18 @@ static int log_notify(struct blob_attr *msg)
> uloop_timeout_set(&retry, 1000);
> }
> } else {
> - snprintf(buf, sizeof(buf), "%s %s%s.%s%s %s\n",
> - c, log_timestamp ? buf_ts : "",
> - getcodetext(LOG_FAC(p) << 3, facilitynames),
> - getcodetext(LOG_PRI(p), prioritynames),
> - (blobmsg_get_u32(tb[LOG_SOURCE])) ? ("") : (" kernel:"), m);
> + if (!log_template) {
> + snprintf(buf, sizeof(buf), "%s %s%s.%s%s %s\n",
> + c, log_timestamp ? buf_ts : "",
> + getcodetext(LOG_FAC(p) << 3, facilitynames),
> + getcodetext(LOG_PRI(p), prioritynames),
> + (blobmsg_get_u32(tb[LOG_SOURCE])) ? ("") : (" kernel:"), m);
> + } else {
> + size_t buflen = strlen(buf);
> + buflen = buflen <= sizeof buf - 2 ? buflen : sizeof buf - 2;
Need parens. Also much more clear as
buflen = (buflen <= (sizeof(buf) - 2)) ? buflen : (sizeof(buf) - 2);
> + buf[buflen] = '\n’;
buflen++ ?
> + buf[buflen+1] = '\0’;
Ditto.
> + }
> ret = write(sender.fd, buf, strlen(buf));
> }
>
> @@ -211,6 +308,7 @@ static int usage(const char *prog)
> " -p <file> PID file\n"
> " -h <hostname> Add hostname to the message\n"
> " -P <prefix> Prefix custom text to streamed messages\n"
> + " -T <template> Custom log output template\n"
> " -f Follow log messages\n"
> " -u Use UDP as the protocol\n"
> " -t Add an extra timestamp\n"
> @@ -260,7 +358,7 @@ int main(int argc, char **argv)
>
> signal(SIGPIPE, SIG_IGN);
>
> - while ((ch = getopt(argc, argv, "u0fcs:l:r:F:p:S:P:h:e:t")) != -1) {
> + while ((ch = getopt(argc, argv, "u0fcs:l:r:F:p:S:P:h:e:tT:")) != -1) {
> switch (ch) {
> case 'u':
> log_udp = 1;
> @@ -307,6 +405,9 @@ int main(int argc, char **argv)
> case 't':
> log_timestamp = 1;
> break;
> + case 'T':
> + log_template = optarg;
> + break;
> default:
> return usage(*argv);
> }
> --
> 2.7.4
>
>
> _______________________________________________
> Lede-dev mailing list
> Lede-dev at lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/lede-dev
More information about the Lede-dev
mailing list