kdb: Refactor env variables get/set code

Add two new kdb environment access methods as kdb_setenv() and
kdb_printenv() in order to abstract out environment access code
from kdb command functions.

Also, replace (char *)0 with NULL as an initializer for environment
variables array.

Signed-off-by: Sumit Garg <[email protected]>
Reviewed-by: Douglas Anderson <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
[[email protected]: Replaced (char *)0/NULL initializers with
an array size]
Signed-off-by: Daniel Thompson <[email protected]>

diff --git a/kernel/debug/kdb/kdb_main.c b/kernel/debug/kdb/kdb_main.c
index 95a1b1f543269f2383fd04b9ad8da02436f0b072..405d24aa51561822e7e2d5860f65792ebb5d37cd 100644 (file)
--- a/kernel/debug/kdb/kdb_main.c
+++ b/kernel/debug/kdb/kdb_main.c
@@ -140,42 +140,18 @@ static const int __nkdb_err = ARRAY_SIZE(kdbmsgs);
  * KDB_ENVBUFSIZE if required).
  */
 
-static char *__env[] = {
+static char *__env[31] = {
 #if defined(CONFIG_SMP)
- "PROMPT=[%d]kdb> ",
+       "PROMPT=[%d]kdb> ",
 #else
- "PROMPT=kdb> ",
+       "PROMPT=kdb> ",
 #endif
- "MOREPROMPT=more> ",
- "RADIX=16",
- "MDCOUNT=8",                  /* lines of md output */
- KDB_PLATFORM_ENV,
- "DTABCOUNT=30",
- "NOSECT=1",
- (char *)0,
- (char *)0,
- (char *)0,
- (char *)0,
- (char *)0,
- (char *)0,
- (char *)0,
- (char *)0,
- (char *)0,
- (char *)0,
- (char *)0,
- (char *)0,
- (char *)0,
- (char *)0,
- (char *)0,
- (char *)0,
- (char *)0,
- (char *)0,
- (char *)0,
- (char *)0,
- (char *)0,
- (char *)0,
- (char *)0,
- (char *)0,
+       "MOREPROMPT=more> ",
+       "RADIX=16",
+       "MDCOUNT=8",            /* lines of md output */
+       KDB_PLATFORM_ENV,
+       "DTABCOUNT=30",
+       "NOSECT=1",
 };
 
 static const int __nenv = ARRAY_SIZE(__env);
@@ -317,6 +293,63 @@ int kdbgetintenv(const char *match, int *value)
        return diag;
 }
 
+/*
+ * kdb_setenv() - Alter an existing environment variable or create a new one.
+ * @var: Name of the variable
+ * @val: Value of the variable
+ *
+ * Return: Zero on success, a kdb diagnostic on failure.
+ */
+static int kdb_setenv(const char *var, const char *val)
+{
+       int i;
+       char *ep;
+       size_t varlen, vallen;
+
+       varlen = strlen(var);
+       vallen = strlen(val);
+       ep = kdballocenv(varlen + vallen + 2);
+       if (ep == (char *)0)
+               return KDB_ENVBUFFULL;
+
+       sprintf(ep, "%s=%s", var, val);
+
+       for (i = 0; i < __nenv; i++) {
+               if (__env[i]
+                && ((strncmp(__env[i], var, varlen) == 0)
+                  && ((__env[i][varlen] == '\0')
+                   || (__env[i][varlen] == '=')))) {
+                       __env[i] = ep;
+                       return 0;
+               }
+       }
+
+       /*
+        * Wasn't existing variable.  Fit into slot.
+        */
+       for (i = 0; i < __nenv-1; i++) {
+               if (__env[i] == (char *)0) {
+                       __env[i] = ep;
+                       return 0;
+               }
+       }
+
+       return KDB_ENVFULL;
+}
+
+/*
+ * kdb_printenv() - Display the current environment variables.
+ */
+static void kdb_printenv(void)
+{
+       int i;
+
+       for (i = 0; i < __nenv; i++) {
+               if (__env[i])
+                       kdb_printf("%s\n", __env[i]);
+       }
+}
+
 /*
  * kdbgetularg - This function will convert a numeric string into an
  *     unsigned long value.
@@ -374,10 +407,6 @@ int kdbgetu64arg(const char *arg, u64 *value)
  */
 int kdb_set(int argc, const char **argv)
 {
-       int i;
-       char *ep;
-       size_t varlen, vallen;
-
        /*
         * we can be invoked two ways:
         *   set var=value    argv[1]="var", argv[2]="value"
@@ -422,37 +451,7 @@ int kdb_set(int argc, const char **argv)
         * Tokenizer squashed the '=' sign.  argv[1] is variable
         * name, argv[2] = value.
         */
-       varlen = strlen(argv[1]);
-       vallen = strlen(argv[2]);
-       ep = kdballocenv(varlen + vallen + 2);
-       if (ep == (char *)0)
-               return KDB_ENVBUFFULL;
-
-       sprintf(ep, "%s=%s", argv[1], argv[2]);
-
-       ep[varlen+vallen+1] = '\0';
-
-       for (i = 0; i < __nenv; i++) {
-               if (__env[i]
-                && ((strncmp(__env[i], argv[1], varlen) == 0)
-                  && ((__env[i][varlen] == '\0')
-                   || (__env[i][varlen] == '=')))) {
-                       __env[i] = ep;
-                       return 0;
-               }
-       }
-
-       /*
-        * Wasn't existing variable.  Fit into slot.
-        */
-       for (i = 0; i < __nenv-1; i++) {
-               if (__env[i] == (char *)0) {
-                       __env[i] = ep;
-                       return 0;
-               }
-       }
-
-       return KDB_ENVFULL;
+       return kdb_setenv(argv[1], argv[2]);
 }
 
 static int kdb_check_regs(void)
@@ -2055,12 +2054,7 @@ static int kdb_lsmod(int argc, const char **argv)
 
 static int kdb_env(int argc, const char **argv)
 {
-       int i;
-
-       for (i = 0; i < __nenv; i++) {
-               if (__env[i])
-                       kdb_printf("%s\n", __env[i]);
-       }
+       kdb_printenv();
 
        if (KDB_DEBUG(MASK))
                kdb_printf("KDBDEBUG=0x%x\n",