Using strncpy() to copy strings is suboptimal because strncpy writes a
bunch of additional unnecessary null bytes. Use snprintf() instead of
strncpy(). An additional advantage of snprintf() is that it guarantees
that the output string is '\0'-terminated.
This patch is an improvement for commit 32e31c8c5f7b ("Fix string copy
compilation warnings").
Cc: Damien Le Moal <damien.lemoal@xxxxxxx>
Signed-off-by: Bart Van Assche <bvanassche@xxxxxxx>
---
cconv.c | 7 +++----
client.c | 5 +++--
diskutil.c | 9 ++++-----
engines/net.c | 6 ++----
engines/sg.c | 4 ++--
filesetup.c | 6 ++----
gclient.c | 4 ++--
init.c | 19 +++++--------------
ioengines.c | 3 +--
options.c | 3 +--
parse.c | 6 ++----
server.c | 26 +++++++++++---------------
stat.c | 15 ++++++++-------
verify.c | 3 +--
14 files changed, 47 insertions(+), 69 deletions(-)
diff --git a/cconv.c b/cconv.c
index 50e45c63a636..0e6572462788 100644
--- a/cconv.c
+++ b/cconv.c
@@ -13,10 +13,9 @@ static void string_to_cpu(char **dst, const uint8_t *src)
static void __string_to_net(uint8_t *dst, const char *src, size_t dst_size)
{
- if (src) {
- dst[dst_size - 1] = '\0';
- strncpy((char *) dst, src, dst_size - 1);
- } else
+ if (src)
+ snprintf((char *) dst, dst_size, "%s", src);
+ else
dst[0] = '\0';
}
diff --git a/client.c b/client.c
index 43cfbd43b9d3..e0047af06a3e 100644
--- a/client.c
+++ b/client.c
@@ -520,7 +520,7 @@ static void probe_client(struct fio_client *client)
sname = server_name(client, buf, sizeof(buf));
memset(pdu.server, 0, sizeof(pdu.server));
- strncpy((char *) pdu.server, sname, sizeof(pdu.server) - 1);
+ snprintf((char *) pdu.server, sizeof(pdu.server), "%s", sname);
fio_net_send_cmd(client->fd, FIO_NET_CMD_PROBE, &pdu, sizeof(pdu), &tag, &client->cmd_list);
}
@@ -574,7 +574,8 @@ static int fio_client_connect_sock(struct fio_client *client)
memset(addr, 0, sizeof(*addr));
addr->sun_family = AF_UNIX;
- strncpy(addr->sun_path, client->hostname, sizeof(addr->sun_path) - 1);
+ snprintf(addr->sun_path, sizeof(addr->sun_path), "%s",
+ client->hostname);
fd = socket(AF_UNIX, SOCK_STREAM, 0);
if (fd < 0) {
diff --git a/diskutil.c b/diskutil.c
index 7be4c022431e..f074401501ba 100644
--- a/diskutil.c
+++ b/diskutil.c
@@ -181,8 +181,7 @@ static int get_device_numbers(char *file_name, int *maj, int *min)
/*
* must be a file, open "." in that path
*/
- tempname[PATH_MAX - 1] = '\0';
- strncpy(tempname, file_name, PATH_MAX - 1);
+ snprintf(tempname, ARRAY_SIZE(tempname), "%s", file_name);
p = dirname(tempname);
if (stat(p, &st)) {
perror("disk util stat");
@@ -314,7 +313,8 @@ static struct disk_util *disk_util_add(struct thread_data *td, int majdev,
sfree(du);
return NULL;
}
- strncpy((char *) du->dus.name, basename(path), FIO_DU_NAME_SZ - 1);
+ snprintf((char *) du->dus.name, ARRAY_SIZE(du->dus.name), "%s",
+ basename(path));
du->sysfs_root = strdup(path);
du->major = majdev;
du->minor = mindev;
@@ -435,8 +435,7 @@ static struct disk_util *__init_per_file_disk_util(struct thread_data *td,
log_err("unknown sysfs layout\n");
return NULL;
}
- tmp[PATH_MAX - 1] = '\0';
- strncpy(tmp, p, PATH_MAX - 1);
+ snprintf(tmp, ARRAY_SIZE(tmp), "%s", p);
sprintf(path, "%s", tmp);
}
diff --git a/engines/net.c b/engines/net.c
index ca6fb344b897..91f25774690a 100644
--- a/engines/net.c
+++ b/engines/net.c
@@ -1105,8 +1105,7 @@ static int fio_netio_setup_connect_unix(struct thread_data *td,
struct sockaddr_un *soun = &nd->addr_un;
soun->sun_family = AF_UNIX;
- memset(soun->sun_path, 0, sizeof(soun->sun_path));
- strncpy(soun->sun_path, path, sizeof(soun->sun_path) - 1);
+ snprintf(soun->sun_path, sizeof(soun->sun_path), "%s", path);
return 0;
}
@@ -1135,9 +1134,8 @@ static int fio_netio_setup_listen_unix(struct thread_data *td, const char *path)
mode = umask(000);
- memset(addr, 0, sizeof(*addr));
addr->sun_family = AF_UNIX;
- strncpy(addr->sun_path, path, sizeof(addr->sun_path) - 1);
+ snprintf(addr->sun_path, sizeof(addr->sun_path), "%s", path);
unlink(path);
len = sizeof(addr->sun_family) + strlen(path) + 1;
diff --git a/engines/sg.c b/engines/sg.c
index c46b9abaec87..a1a6de4ce248 100644
--- a/engines/sg.c
+++ b/engines/sg.c
@@ -1181,8 +1181,8 @@ static char *fio_sgio_errdetails(struct io_u *io_u)
}
if (!(hdr->info & SG_INFO_CHECK) && !strlen(msg))
- strncpy(msg, "SG Driver did not report a Host, Driver or Device check",
- MAXERRDETAIL - 1);
+ snprintf(msg, MAXERRDETAIL, "%s",
+ "SG Driver did not report a Host, Driver or Device check");
return msg;
}
diff --git a/filesetup.c b/filesetup.c
index 17fa31fb3cd4..57eca1bf5bf0 100644
--- a/filesetup.c
+++ b/filesetup.c
@@ -805,8 +805,7 @@ static unsigned long long get_fs_free_counts(struct thread_data *td)
} else if (f->filetype != FIO_TYPE_FILE)
continue;
- buf[255] = '\0';
- strncpy(buf, f->file_name, 255);
+ snprintf(buf, ARRAY_SIZE(buf), "%s", f->file_name);
if (stat(buf, &sb) < 0) {
if (errno != ENOENT)
@@ -829,8 +828,7 @@ static unsigned long long get_fs_free_counts(struct thread_data *td)
continue;
fm = calloc(1, sizeof(*fm));
- strncpy(fm->__base, buf, sizeof(fm->__base));
- fm->__base[255] = '\0';
+ snprintf(fm->__base, ARRAY_SIZE(fm->__base), "%s", buf);
fm->base = basename(fm->__base);
fm->key = sb.st_dev;
flist_add(&fm->list, &list);
diff --git a/gclient.c b/gclient.c
index 04275a1384c2..64324177ef1a 100644
--- a/gclient.c
+++ b/gclient.c
@@ -318,7 +318,7 @@ static void gfio_update_thread_status(struct gui_entry *ge,
static char message[100];
const char *m = message;
- strncpy(message, status_message, sizeof(message) - 1);
+ snprintf(message, sizeof(message), "%s", status_message);
gtk_progress_bar_set_text(GTK_PROGRESS_BAR(ge->thread_status_pb), m);
gtk_progress_bar_set_fraction(GTK_PROGRESS_BAR(ge->thread_status_pb), perc / 100.0);
gtk_widget_queue_draw(ge->ui->window);
@@ -330,7 +330,7 @@ static void gfio_update_thread_status_all(struct gui *ui, char *status_message,
static char message[100];
const char *m = message;
- strncpy(message, status_message, sizeof(message) - 1);
+ strncpy(message, sizeof(message), "%s", status_message);
gtk_progress_bar_set_text(GTK_PROGRESS_BAR(ui->thread_status_pb), m);
gtk_progress_bar_set_fraction(GTK_PROGRESS_BAR(ui->thread_status_pb), perc / 100.0);
gtk_widget_queue_draw(ui->window);
diff --git a/init.c b/init.c
index c9f6198ea63a..63f2168eabcb 100644
--- a/init.c
+++ b/init.c
@@ -1273,8 +1273,7 @@ static char *make_filename(char *buf, size_t buf_size,struct thread_options *o,
for (f = &fpre_keywords[0]; f->keyword; f++)
f->strlen = strlen(f->keyword);
- buf[buf_size - 1] = '\0';
- strncpy(buf, o->filename_format, buf_size - 1);
+ snprintf(buf, buf_size, "%s", o->filename_format);
memset(copy, 0, sizeof(copy));
for (f = &fpre_keywords[0]; f->keyword; f++) {
@@ -1353,7 +1352,7 @@ static char *make_filename(char *buf, size_t buf_size,struct thread_options *o,
if (post_start)
strncpy(dst, buf + post_start, dst_left);
- strncpy(buf, copy, buf_size - 1);
+ snprintf(buf, buf_size, "%s", copy);
} while (1);
}
@@ -2029,20 +2028,12 @@ static int __parse_jobs_ini(struct thread_data *td,
*/
if (access(filename, F_OK) &&
(ts = strrchr(file, '/'))) {
- int len = ts - file +
- strlen(filename) + 2;
-
- if (!(full_fn = calloc(1, len))) {
+ if (asprintf(&full_fn, "%.*s%s",
+ (int)(ts - file + 1), file,
+ filename) < 0) {
ret = ENOMEM;
break;
}
-
- strncpy(full_fn,
- file, (ts - file) + 1);
- strncpy(full_fn + (ts - file) + 1,
- filename,
- len - (ts - file) - 1);
- full_fn[len - 1] = 0;
filename = full_fn;
}
diff --git a/ioengines.c b/ioengines.c
index aa4ccd2755c9..40fa75c382b4 100644
--- a/ioengines.c
+++ b/ioengines.c
@@ -125,8 +125,7 @@ static struct ioengine_ops *__load_ioengine(const char *name)
{
char engine[64];
- engine[sizeof(engine) - 1] = '\0';
- strncpy(engine, name, sizeof(engine) - 1);
+ snprintf(engine, sizeof(engine), "%s", name);
/*
* linux libaio has alias names, so convert to what we want
diff --git a/options.c b/options.c
index f4c9bedf377f..447f231e7148 100644
--- a/options.c
+++ b/options.c
@@ -4902,8 +4902,7 @@ char *fio_option_dup_subs(const char *opt)
return NULL;
}
- in[OPT_LEN_MAX] = '\0';
- strncpy(in, opt, OPT_LEN_MAX);
+ snprintf(in, sizeof(in), "%s", opt);
while (*inptr && nchr > 0) {
if (inptr[0] == '$' && inptr[1] == '{') {
diff --git a/parse.c b/parse.c
index a7d4516e4702..c4fd4626df9f 100644
--- a/parse.c
+++ b/parse.c
@@ -602,8 +602,7 @@ static int __handle_option(const struct fio_option *o, const char *ptr,
if (!is_time && o->is_time)
is_time = o->is_time;
- tmp[sizeof(tmp) - 1] = '\0';
- strncpy(tmp, ptr, sizeof(tmp) - 1);
+ snprintf(tmp, sizeof(tmp), "%s", ptr);
p = strchr(tmp, ',');
if (p)
*p = '\0';
@@ -829,8 +828,7 @@ static int __handle_option(const struct fio_option *o, const char *ptr,
char tmp[128];
char *p1, *p2;
- tmp[sizeof(tmp) - 1] = '\0';
- strncpy(tmp, ptr, sizeof(tmp) - 1);
+ snprintf(tmp, sizeof(tmp), "%s", ptr);
/* Handle bsrange with separate read,write values: */
p1 = strchr(tmp, ',');
diff --git a/server.c b/server.c
index 23e549a590a7..e7846227f2b1 100644
--- a/server.c
+++ b/server.c
@@ -865,7 +865,8 @@ static int handle_probe_cmd(struct fio_net_cmd *cmd)
strcpy(me, (char *) pdu->server);
gethostname((char *) probe.hostname, sizeof(probe.hostname));
- strncpy((char *) probe.fio_version, fio_version_string, sizeof(probe.fio_version) - 1);
+ snprintf((char *) probe.fio_version, sizeof(probe.fio_version), "%s",
+ fio_version_string);
/*
* If the client supports compression and we do too, then enable it
@@ -1470,12 +1471,10 @@ void fio_server_send_ts(struct thread_stat *ts, struct group_run_stats *rs)
memset(&p, 0, sizeof(p));
- strncpy(p.ts.name, ts->name, FIO_JOBNAME_SIZE);
- p.ts.name[FIO_JOBNAME_SIZE - 1] = '\0';
- strncpy(p.ts.verror, ts->verror, FIO_VERROR_SIZE);
- p.ts.verror[FIO_VERROR_SIZE - 1] = '\0';
- strncpy(p.ts.description, ts->description, FIO_JOBDESC_SIZE);
- p.ts.description[FIO_JOBDESC_SIZE - 1] = '\0';
+ snprintf(p.ts.name, sizeof(p.ts.name), "%s", ts->name);
+ snprintf(p.ts.verror, sizeof(p.ts.verror), "%s", ts->verror);
+ snprintf(p.ts.description, sizeof(p.ts.description), "%s",
+ ts->description);
p.ts.error = cpu_to_le32(ts->error);
p.ts.thread_number = cpu_to_le32(ts->thread_number);
@@ -1666,8 +1665,7 @@ static void convert_dus(struct disk_util_stat *dst, struct disk_util_stat *src)
{
int i;
- dst->name[FIO_DU_NAME_SZ - 1] = '\0';
- strncpy((char *) dst->name, (char *) src->name, FIO_DU_NAME_SZ - 1);
+ snprintf((char *) dst->name, sizeof(dst->name), "%s", src->name);
for (i = 0; i < 2; i++) {
dst->s.ios[i] = cpu_to_le64(src->s.ios[i]);
@@ -1977,8 +1975,7 @@ int fio_send_iolog(struct thread_data *td, struct io_log *log, const char *name)
else
pdu.compressed = 0;
- strncpy((char *) pdu.name, name, FIO_NET_NAME_MAX);
- pdu.name[FIO_NET_NAME_MAX - 1] = '\0';
+ snprintf((char *) pdu.name, sizeof(pdu.name), "%s", name);
/*
* We can't do this for a pre-compressed log, but for that case,
@@ -2195,9 +2192,8 @@ static int fio_init_server_sock(void)
mode = umask(000);
- memset(&addr, 0, sizeof(addr));
addr.sun_family = AF_UNIX;
- strncpy(addr.sun_path, bind_sock, sizeof(addr.sun_path) - 1);
+ snprintf(addr.sun_path, sizeof(addr.sun_path), "%s", bind_sock);
len = sizeof(addr.sun_family) + strlen(bind_sock) + 1;
@@ -2247,9 +2243,9 @@ static int fio_init_server_connection(void)
if (p)
strcat(p, port);
else
- strncpy(bind_str, port, sizeof(bind_str) - 1);
+ snprintf(bind_str, sizeof(bind_str), "%s", port);
} else
- strncpy(bind_str, bind_sock, sizeof(bind_str) - 1);
+ snprintf(bind_str, sizeof(bind_str), "%s", bind_sock);
log_info("fio: server listening on %s\n", bind_str);
diff --git a/stat.c b/stat.c
index bf87917c2956..33637900df62 100644
--- a/stat.c
+++ b/stat.c
@@ -1828,10 +1828,11 @@ void __show_run_stats(void)
/*
* These are per-group shared already
*/
- strncpy(ts->name, td->o.name, FIO_JOBNAME_SIZE - 1);
+ snprintf(ts->name, sizeof(ts->name), "%s", td->o.name);
if (td->o.description)
- strncpy(ts->description, td->o.description,
- FIO_JOBDESC_SIZE - 1);
+ snprintf(ts->description,
+ sizeof(ts->description), "%s",
+ td->o.description);
else
memset(ts->description, 0, FIO_JOBDESC_SIZE);
@@ -1868,12 +1869,12 @@ void __show_run_stats(void)
if (!td->error && td->o.continue_on_error &&
td->first_error) {
ts->error = td->first_error;
- ts->verror[sizeof(ts->verror) - 1] = '\0';
- strncpy(ts->verror, td->verror, sizeof(ts->verror) - 1);
+ snprintf(ts->verror, sizeof(ts->verror), "%s",
+ td->verror);
} else if (td->error) {
ts->error = td->error;
- ts->verror[sizeof(ts->verror) - 1] = '\0';
- strncpy(ts->verror, td->verror, sizeof(ts->verror) - 1);
+ snprintf(ts->verror, sizeof(ts->verror), "%s",
+ td->verror);
}
}
diff --git a/verify.c b/verify.c
index f79ab43aab6b..48ba051da3ad 100644
--- a/verify.c
+++ b/verify.c
@@ -1635,8 +1635,7 @@ struct all_io_list *get_all_io_list(int save_mask, size_t *sz)
s->rand.state32.s[3] = 0;
s->rand.use64 = 0;
}
- s->name[sizeof(s->name) - 1] = '\0';
- strncpy((char *) s->name, td->o.name, sizeof(s->name) - 1);
+ snprintf((char *) s->name, sizeof(s->name), "%s", td->o.name);
next = io_list_next(s);
}
--
2.22.0
