* [PATCH iproute2 1/2] lib: utils: introduce scnprintf @ 2024-02-09 9:36 Denis Kirjanov 2024-02-09 9:36 ` [PATCH iproute2 2/2] ifstat: convert string formatting calls to scnprintf Denis Kirjanov 2024-02-09 16:33 ` [PATCH iproute2 1/2] lib: utils: introduce scnprintf Stephen Hemminger 0 siblings, 2 replies; 4+ messages in thread From: Denis Kirjanov @ 2024-02-09 9:36 UTC (permalink / raw) To: stephen, dsahern; +Cc: netdev, Denis Kirjanov The function is similar to the standard snprintf but returns the number of characters actually written to @buf argument excluding the trailing '\0' Signed-off-by: Denis Kirjanov <dkirjanov@suse.de> --- include/utils.h | 1 + lib/utils.c | 14 ++++++++++++++ 2 files changed, 15 insertions(+) diff --git a/include/utils.h b/include/utils.h index 9ba129b8..5b65edc5 100644 --- a/include/utils.h +++ b/include/utils.h @@ -393,4 +393,5 @@ int proto_a2n(unsigned short *id, const char *buf, const char *proto_n2a(unsigned short id, char *buf, int len, const struct proto *proto_tb, size_t tb_len); +int scnprintf(char * buf, size_t size, const char * fmt, ...); #endif /* __UTILS_H__ */ diff --git a/lib/utils.c b/lib/utils.c index 6c1c1a8d..752da66f 100644 --- a/lib/utils.c +++ b/lib/utils.c @@ -7,6 +7,7 @@ #include <stdio.h> #include <stdlib.h> +#include <stdarg.h> #include <math.h> #include <unistd.h> #include <fcntl.h> @@ -2003,3 +2004,16 @@ int proto_a2n(unsigned short *id, const char *buf, return 0; } + +int scnprintf(char * buf, size_t size, const char * fmt, ...) +{ + ssize_t ssize = size; + va_list args; + int i; + + va_start(args, fmt); + i = vsnprintf(buf, size, fmt, args); + va_end(args); + + return (i >= ssize) ? (ssize - 1) : i; +} -- 2.30.2 ^ permalink raw reply related [flat|nested] 4+ messages in thread
* [PATCH iproute2 2/2] ifstat: convert string formatting calls to scnprintf 2024-02-09 9:36 [PATCH iproute2 1/2] lib: utils: introduce scnprintf Denis Kirjanov @ 2024-02-09 9:36 ` Denis Kirjanov 2024-02-09 16:33 ` [PATCH iproute2 1/2] lib: utils: introduce scnprintf Stephen Hemminger 1 sibling, 0 replies; 4+ messages in thread From: Denis Kirjanov @ 2024-02-09 9:36 UTC (permalink / raw) To: stephen, dsahern; +Cc: netdev, Denis Kirjanov Use scnprintf to print only valid data Signed-off-by: Denis Kirjanov <dkirjanov@suse.de> --- misc/ifstat.c | 18 +++++++++--------- 1 file changed, 9 insertions(+), 9 deletions(-) diff --git a/misc/ifstat.c b/misc/ifstat.c index 721f4914..288e9064 100644 --- a/misc/ifstat.c +++ b/misc/ifstat.c @@ -379,10 +379,10 @@ static void format_rate(FILE *fp, const unsigned long long *vals, fprintf(fp, "%8llu ", vals[i]); if (rates[i] > mega) { - sprintf(temp, "%uM", (unsigned int)(rates[i]/mega)); + scnprintf(temp, sizeof(temp), "%uM", (unsigned int)(rates[i]/mega)); fprintf(fp, "%-6s ", temp); } else if (rates[i] > kilo) { - sprintf(temp, "%uK", (unsigned int)(rates[i]/kilo)); + scnprintf(temp, sizeof(temp), "%uK", (unsigned int)(rates[i]/kilo)); fprintf(fp, "%-6s ", temp); } else fprintf(fp, "%-6u ", (unsigned int)rates[i]); @@ -400,10 +400,10 @@ static void format_pair(FILE *fp, const unsigned long long *vals, int i, int k) fprintf(fp, "%8llu ", vals[i]); if (vals[k] > giga) { - sprintf(temp, "%uM", (unsigned int)(vals[k]/mega)); + scnprintf(temp, sizeof(temp), "%uM", (unsigned int)(vals[k]/mega)); fprintf(fp, "%-6s ", temp); } else if (vals[k] > mega) { - sprintf(temp, "%uK", (unsigned int)(vals[k]/kilo)); + scnprintf(temp, sizeof(temp), "%uK", (unsigned int)(vals[k]/kilo)); fprintf(fp, "%-6s ", temp); } else fprintf(fp, "%-6u ", (unsigned int)vals[k]); @@ -675,7 +675,7 @@ static void server_loop(int fd) p.fd = fd; p.events = p.revents = POLLIN; - sprintf(info_source, "%d.%lu sampling_interval=%d time_const=%d", + scnprintf(info_source, sizeof(info_source), "%d.%lu sampling_interval=%d time_const=%d", getpid(), (unsigned long)random(), scan_interval/1000, time_constant/1000); load_info(); @@ -893,7 +893,7 @@ int main(int argc, char *argv[]) sun.sun_family = AF_UNIX; sun.sun_path[0] = 0; - sprintf(sun.sun_path+1, "ifstat%d", getuid()); + scnprintf(sun.sun_path + 1, sizeof(sun.sun_path) - 1, "ifstat%d", getuid()); if (scan_interval > 0) { if (time_constant == 0) @@ -926,14 +926,14 @@ int main(int argc, char *argv[]) npatterns = argc; if (getenv("IFSTAT_HISTORY")) - snprintf(hist_name, sizeof(hist_name), + scnprintf(hist_name, sizeof(hist_name), "%s", getenv("IFSTAT_HISTORY")); else if (!stats_type) - snprintf(hist_name, sizeof(hist_name), + scnprintf(hist_name, sizeof(hist_name), "%s/.ifstat.u%d", P_tmpdir, getuid()); else - snprintf(hist_name, sizeof(hist_name), + scnprintf(hist_name, sizeof(hist_name), "%s/.%s_ifstat.u%d", P_tmpdir, stats_type, getuid()); -- 2.30.2 ^ permalink raw reply related [flat|nested] 4+ messages in thread
* Re: [PATCH iproute2 1/2] lib: utils: introduce scnprintf 2024-02-09 9:36 [PATCH iproute2 1/2] lib: utils: introduce scnprintf Denis Kirjanov 2024-02-09 9:36 ` [PATCH iproute2 2/2] ifstat: convert string formatting calls to scnprintf Denis Kirjanov @ 2024-02-09 16:33 ` Stephen Hemminger 2024-02-10 8:37 ` Denis Kirjanov 1 sibling, 1 reply; 4+ messages in thread From: Stephen Hemminger @ 2024-02-09 16:33 UTC (permalink / raw) To: Denis Kirjanov; +Cc: dsahern, netdev, Denis Kirjanov On Fri, 9 Feb 2024 04:36:18 -0500 Denis Kirjanov <kirjanov@gmail.com> wrote: > The function is similar to the standard snprintf but > returns the number of characters actually written to @buf > argument excluding the trailing '\0' > > Signed-off-by: Denis Kirjanov <dkirjanov@suse.de> > --- I don't understand, why not use snprintf in ifstat? None of the cases in patch 2 care about the return value length. ^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [PATCH iproute2 1/2] lib: utils: introduce scnprintf 2024-02-09 16:33 ` [PATCH iproute2 1/2] lib: utils: introduce scnprintf Stephen Hemminger @ 2024-02-10 8:37 ` Denis Kirjanov 0 siblings, 0 replies; 4+ messages in thread From: Denis Kirjanov @ 2024-02-10 8:37 UTC (permalink / raw) To: Stephen Hemminger, Denis Kirjanov; +Cc: dsahern, netdev On 2/9/24 19:33, Stephen Hemminger wrote: > On Fri, 9 Feb 2024 04:36:18 -0500 > Denis Kirjanov <kirjanov@gmail.com> wrote: > >> The function is similar to the standard snprintf but >> returns the number of characters actually written to @buf >> argument excluding the trailing '\0' >> >> Signed-off-by: Denis Kirjanov <dkirjanov@suse.de> >> --- > > I don't understand, why not use snprintf in ifstat? > None of the cases in patch 2 care about the return value length. Hi Stephen, My intention is just use one safe version of the string formatting function. I'm going to convert other places as well. ^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2024-02-10 8:37 UTC | newest] Thread overview: 4+ messages (download: mbox.gz follow: Atom feed -- links below jump to the message on this page -- 2024-02-09 9:36 [PATCH iproute2 1/2] lib: utils: introduce scnprintf Denis Kirjanov 2024-02-09 9:36 ` [PATCH iproute2 2/2] ifstat: convert string formatting calls to scnprintf Denis Kirjanov 2024-02-09 16:33 ` [PATCH iproute2 1/2] lib: utils: introduce scnprintf Stephen Hemminger 2024-02-10 8:37 ` Denis Kirjanov
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