[PATCH v2 6/9] nvme: convert some function arguments from "char *" to "const char *"

[mwilck at suse.com]

From: Martin Wilck <mwilck at suse.com>

Make some function arguments "const char *" where possible. This
is generally desirable and allows passing string constants to these
function.

Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni at wdc.com>
Reviewed-by: Sagi Grimberg <sagi at grimberg.me>
Signed-off-by: Martin Wilck <mwilck at suse.com>
---
 fabrics.c       | 25 +++++++++++++++----------
 nvme-topology.c |  2 +-
 nvme.c          |  2 +-
 nvme.h          |  4 ++--
 4 files changed, 19 insertions(+), 14 deletions(-)

diff --git a/fabrics.c b/fabrics.c
index 1aa1507..4a5c2f9 100644
--- a/fabrics.c
+++ b/fabrics.c
@@ -234,7 +234,7 @@ static int do_discover(char *argstr, bool connect, enum nvme_print_flags flags);
  * If field found, return string containing field value. If field
  * not found, return an empty string.
  */
-static char *parse_conn_arg(char *conargs, const char delim, const char *field)
+static char *parse_conn_arg(const char *conargs, const char delim, const char *field)
 {
 	char *s, *e;
 	size_t cnt;
@@ -278,17 +278,22 @@ empty_field:
 	return strdup("\0");
 }
 
-static int ctrl_instance(char *device)
+static int ctrl_instance(const char *device)
 {
 	char d[64];
+	const char *p;
 	int ret, instance;
 
-	device = basename(device);
-	ret = sscanf(device, "nvme%d", &instance);
+	p = strrchr(device, '/');
+	if (p == NULL)
+		p = device;
+	else
+		p++;
+	ret = sscanf(p, "nvme%d", &instance);
 	if (ret <= 0)
 		return -EINVAL;
 	if (snprintf(d, sizeof(d), "nvme%d", instance) <= 0 ||
-	    strcmp(device, d))
+	    strcmp(p, d))
 		return -EINVAL;
 	return instance;
 }
@@ -299,7 +304,7 @@ static int ctrl_instance(char *device)
  * given.
  * Return true/false based on whether it matches
  */
-static bool ctrl_matches_connectargs(char *name, struct connect_args *args)
+static bool ctrl_matches_connectargs(const char *name, struct connect_args *args)
 {
 	struct connect_args cargs;
 	bool found = false;
@@ -924,7 +929,7 @@ add_int_argument(char **argstr, int *max_len, char *arg_str, int arg,
 }
 
 static int
-add_argument(char **argstr, int *max_len, char *arg_str, char *arg)
+add_argument(char **argstr, int *max_len, char *arg_str, const char *arg)
 {
 	int len;
 
@@ -1675,7 +1680,7 @@ static int scan_sys_nvme_filter(const struct dirent *d)
 /*
  * Returns 1 if disconnect occurred, 0 otherwise.
  */
-static int disconnect_subsys(char *nqn, char *ctrl)
+static int disconnect_subsys(const char *nqn, char *ctrl)
 {
 	char *sysfs_nqn_path = NULL, *sysfs_del_path = NULL;
 	char subsysnqn[NVMF_NQN_SIZE] = {};
@@ -1713,7 +1718,7 @@ static int disconnect_subsys(char *nqn, char *ctrl)
 /*
  * Returns the number of controllers successfully disconnected.
  */
-static int disconnect_by_nqn(char *nqn)
+static int disconnect_by_nqn(const char *nqn)
 {
 	struct dirent **devices = NULL;
 	int i, n, ret = 0;
@@ -1735,7 +1740,7 @@ static int disconnect_by_nqn(char *nqn)
 	return ret;
 }
 
-static int disconnect_by_device(char *device)
+static int disconnect_by_device(const char *device)
 {
 	int instance;
 
diff --git a/nvme-topology.c b/nvme-topology.c
index 63e433d..c2c9b38 100644
--- a/nvme-topology.c
+++ b/nvme-topology.c
@@ -46,7 +46,7 @@ close_fd:
 	return subsysnqn;
 }
 
-char *nvme_get_ctrl_attr(char *path, const char *attr)
+char *nvme_get_ctrl_attr(const char *path, const char *attr)
 {
 	char *attrpath, *value;
 	ssize_t ret;
diff --git a/nvme.c b/nvme.c
index 8751ffd..bf18366 100644
--- a/nvme.c
+++ b/nvme.c
@@ -209,7 +209,7 @@ int parse_and_open(int argc, char **argv, const char *desc,
 	return ret;
 }
 
-enum nvme_print_flags validate_output_format(char *format)
+enum nvme_print_flags validate_output_format(const char *format)
 {
 	if (!format)
 		return -EINVAL;
diff --git a/nvme.h b/nvme.h
index 8501754..1293d4d 100644
--- a/nvme.h
+++ b/nvme.h
@@ -91,7 +91,7 @@ int parse_and_open(int argc, char **argv, const char *desc,
 extern const char *devicename;
 extern const char *output_format;
 
-enum nvme_print_flags validate_output_format(char *format);
+enum nvme_print_flags validate_output_format(const char *format);
 int __id_ctrl(int argc, char **argv, struct command *cmd,
 	struct plugin *plugin, void (*vs)(__u8 *vs, struct json_object *root));
 char *nvme_char_from_block(char *block);
@@ -109,7 +109,7 @@ int scan_subsystems(struct nvme_topology *t, const char *subsysnqn,
 		    __u32 ns_instance, int nsid, char *dev_dir);
 void free_topology(struct nvme_topology *t);
 char *get_nvme_subsnqn(char *path);
-char *nvme_get_ctrl_attr(char *path, const char *attr);
+char *nvme_get_ctrl_attr(const char *path, const char *attr);
 
 void *nvme_alloc(size_t len, bool *huge);
 void nvme_free(void *p, bool huge);
-- 
2.30.1