[PATCH v2 17/20] lib: move/rename strnicmp() to strncasecmp()

[Jan Beulich <jbeulich@suse.com>]

While moving the implementation, also rename it to match strcasecmp(),
allowing the similar use of a compiler builting in this case as well.

Allow the function to be individually linkable, discardable, and
overridable.

Signed-off-by: Jan Beulich <jbeulich@suse.com>

--- a/xen/arch/arm/domain_build.c
+++ b/xen/arch/arm/domain_build.c
@@ -1224,8 +1224,8 @@ static int __init map_range_to_domain(co
      * They are not MMIO and therefore a domain should not be able to
      * manage them via the IOMEM interface.
      */
-    if ( strnicmp(dt_node_full_name(dev), "/reserved-memory/",
-         strlen("/reserved-memory/")) != 0 )
+    if ( strncasecmp(dt_node_full_name(dev), "/reserved-memory/",
+                     strlen("/reserved-memory/")) != 0 )
     {
         res = iomem_permit_access(d, paddr_to_pfn(addr),
                 paddr_to_pfn(PAGE_ALIGN(addr + len - 1)));
--- a/xen/common/string.c
+++ b/xen/common/string.c
@@ -8,39 +8,6 @@
 #include <xen/string.h>
 #include <xen/ctype.h>
 
-#ifndef __HAVE_ARCH_STRNICMP
-/**
- * strnicmp - Case insensitive, length-limited string comparison
- * @s1: One string
- * @s2: The other string
- * @len: the maximum number of characters to compare
- */
-int strnicmp(const char *s1, const char *s2, size_t len)
-{
-	/* Yes, Virginia, it had better be unsigned */
-	unsigned char c1, c2;
-
-	c1 = 0;	c2 = 0;
-	if (len) {
-		do {
-			c1 = *s1; c2 = *s2;
-			s1++; s2++;
-			if (!c1)
-				break;
-			if (!c2)
-				break;
-			if (c1 == c2)
-				continue;
-			c1 = tolower(c1);
-			c2 = tolower(c2);
-			if (c1 != c2)
-				break;
-		} while (--len);
-	}
-	return (int)c1 - (int)c2;
-}
-#endif
-
 #ifndef __HAVE_ARCH_STRSPN
 /**
  * strspn - Calculate the length of the initial substring of @s which only
--- a/xen/drivers/acpi/pmstat.c
+++ b/xen/drivers/acpi/pmstat.c
@@ -275,14 +275,14 @@ static int get_cpufreq_para(struct xen_s
         strlcpy(op->u.get_para.scaling_governor, "Unknown", CPUFREQ_NAME_LEN);
 
     /* governor specific para */
-    if ( !strnicmp(op->u.get_para.scaling_governor, 
-                   "userspace", CPUFREQ_NAME_LEN) )
+    if ( !strncasecmp(op->u.get_para.scaling_governor,
+                      "userspace", CPUFREQ_NAME_LEN) )
     {
         op->u.get_para.u.userspace.scaling_setspeed = policy->cur;
     }
 
-    if ( !strnicmp(op->u.get_para.scaling_governor, 
-                   "ondemand", CPUFREQ_NAME_LEN) )
+    if ( !strncasecmp(op->u.get_para.scaling_governor,
+                      "ondemand", CPUFREQ_NAME_LEN) )
     {
         ret = get_cpufreq_ondemand_para(
             &op->u.get_para.u.ondemand.sampling_rate_max,
@@ -350,8 +350,8 @@ static int set_cpufreq_para(struct xen_s
     {
         unsigned int freq =op->u.set_para.ctrl_value;
 
-        if ( !strnicmp(policy->governor->name,
-                       "userspace", CPUFREQ_NAME_LEN) )
+        if ( !strncasecmp(policy->governor->name,
+                          "userspace", CPUFREQ_NAME_LEN) )
             ret = write_userspace_scaling_setspeed(op->cpuid, freq);
         else
             ret = -EINVAL;
@@ -363,8 +363,8 @@ static int set_cpufreq_para(struct xen_s
     {
         unsigned int sampling_rate = op->u.set_para.ctrl_value;
 
-        if ( !strnicmp(policy->governor->name,
-                       "ondemand", CPUFREQ_NAME_LEN) )
+        if ( !strncasecmp(policy->governor->name,
+                          "ondemand", CPUFREQ_NAME_LEN) )
             ret = write_ondemand_sampling_rate(sampling_rate);
         else
             ret = -EINVAL;
@@ -376,8 +376,8 @@ static int set_cpufreq_para(struct xen_s
     {
         unsigned int up_threshold = op->u.set_para.ctrl_value;
 
-        if ( !strnicmp(policy->governor->name,
-                       "ondemand", CPUFREQ_NAME_LEN) )
+        if ( !strncasecmp(policy->governor->name,
+                          "ondemand", CPUFREQ_NAME_LEN) )
             ret = write_ondemand_up_threshold(up_threshold);
         else
             ret = -EINVAL;
--- a/xen/drivers/cpufreq/cpufreq.c
+++ b/xen/drivers/cpufreq/cpufreq.c
@@ -111,7 +111,7 @@ struct cpufreq_governor *__find_governor
         return NULL;
 
     list_for_each_entry(t, &cpufreq_governor_list, governor_list)
-        if (!strnicmp(governor, t->name, CPUFREQ_NAME_LEN))
+        if (!strncasecmp(governor, t->name, CPUFREQ_NAME_LEN))
             return t;
 
     return NULL;
--- a/xen/include/xen/string.h
+++ b/xen/include/xen/string.h
@@ -16,8 +16,8 @@ size_t strlcpy(char *, const char *, siz
 size_t strlcat(char *, const char *, size_t);
 int strcmp(const char *, const char *);
 int strncmp(const char *, const char *, size_t);
-int strnicmp(const char *, const char *, size_t);
 int strcasecmp(const char *, const char *);
+int strncasecmp(const char *, const char *, size_t);
 char *strchr(const char *, int);
 char *strrchr(const char *, int);
 char *strstr(const char *, const char *);
@@ -48,6 +48,10 @@ void *memchr_inv(const void *, int, size
 #define strcasecmp(s1, s2) __builtin_strcasecmp(s1, s2)
 #endif
 
+#ifndef __HAVE_ARCH_STRCASECMP
+#define strncasecmp(s1, s2, n) __builtin_strncasecmp(s1, s2, n)
+#endif
+
 #ifndef __HAVE_ARCH_STRCHR
 #define strchr(s1, c) __builtin_strchr(s1, c)
 #endif
--- a/xen/lib/Makefile
+++ b/xen/lib/Makefile
@@ -20,6 +20,7 @@ lib-y += strcmp.o
 lib-y += strlcat.o
 lib-y += strlcpy.o
 lib-y += strlen.o
+lib-y += strncasecmp.o
 lib-y += strncmp.o
 lib-y += strnlen.o
 lib-y += strrchr.o
--- /dev/null
+++ b/xen/lib/strncasecmp.c
@@ -0,0 +1,47 @@
+/*
+ *  Copyright (C) 1991, 1992  Linus Torvalds
+ */
+
+#include <xen/string.h>
+#include <xen/ctype.h>
+
+/**
+ * strncasecmp - Case insensitive, length-limited string comparison
+ * @s1: One string
+ * @s2: The other string
+ * @len: the maximum number of characters to compare
+ */
+int (strncasecmp)(const char *s1, const char *s2, size_t len)
+{
+	/* Yes, Virginia, it had better be unsigned */
+	unsigned char c1, c2;
+
+	c1 = 0;	c2 = 0;
+	if (len) {
+		do {
+			c1 = *s1; c2 = *s2;
+			s1++; s2++;
+			if (!c1)
+				break;
+			if (!c2)
+				break;
+			if (c1 == c2)
+				continue;
+			c1 = tolower(c1);
+			c2 = tolower(c2);
+			if (c1 != c2)
+				break;
+		} while (--len);
+	}
+	return (int)c1 - (int)c2;
+}
+
+/*
+ * Local variables:
+ * mode: C
+ * c-file-style: "BSD"
+ * c-basic-offset: 8
+ * tab-width: 8
+ * indent-tabs-mode: t
+ * End:
+ */