Merge patch series "some string cleanup, and a tweak of the "config" command"

Rasmus Villemoes <[email protected]> says:

This started by me wanting something like what patch 8 does. That
wasn't too hard, except we had no strcasestr(), and also our regex
engine (which I didn't really want to pull into the mix anyway)
doesn't have a flag that requests case-insensitive matching. So I
wanted to add strcasestr(), but then I stumbled on a bunch of stuff
that should be cleaned up in str-land.

Link: https://lore.kernel.org/r/[email protected]

8 files changed, 146 insertions, 107 deletions

diff --git a/arch/sh/include/asm/string.h b/arch/sh/include/asm/string.h
index 999febcb6b7..12a9a8f796c 100644
--- a/arch/sh/include/asm/string.h
+++ b/arch/sh/include/asm/string.h
@@ -8,8 +8,6 @@
  * from linux kernel code.
  */
 
-#ifdef __KERNEL__               /* only set these up for kernel code */
-
 #define __HAVE_ARCH_STRCPY
 static inline char *strcpy(char *__dest, const char *__src)
 {
@@ -81,53 +79,4 @@ static inline int strcmp(const char *__cs, const char *__ct)
 	return __res;
 }
 
-#undef __HAVE_ARCH_STRNCMP
-extern int strncmp(const char *__cs, const char *__ct, size_t __n);
-
-#undef __HAVE_ARCH_MEMSET
-extern void *memset(void *__s, int __c, size_t __count);
-
-#undef __HAVE_ARCH_MEMCPY
-extern void *memcpy(void *__to, __const__ void *__from, size_t __n);
-
-#undef __HAVE_ARCH_MEMMOVE
-extern void *memmove(void *__dest, __const__ void *__src, size_t __n);
-
-#undef __HAVE_ARCH_MEMCHR
-extern void *memchr(const void *__s, int __c, size_t __n);
-
-#undef __HAVE_ARCH_STRLEN
-extern size_t strlen(const char *);
-
-/* arch/sh/lib/strcasecmp.c */
-extern int strcasecmp(const char *, const char *);
-
-#else                           /* KERNEL */
-
-/*
- * let user libraries deal with these,
- * IMHO the kernel has no place defining these functions for user apps
- */
-
-#define __HAVE_ARCH_STRCPY      1
-#define __HAVE_ARCH_STRNCPY     1
-#define __HAVE_ARCH_STRCAT      1
-#define __HAVE_ARCH_STRNCAT     1
-#define __HAVE_ARCH_STRCMP      1
-#define __HAVE_ARCH_STRNCMP     1
-#define __HAVE_ARCH_STRNICMP    1
-#define __HAVE_ARCH_STRCHR      1
-#define __HAVE_ARCH_STRRCHR     1
-#define __HAVE_ARCH_STRSTR      1
-#define __HAVE_ARCH_STRLEN      1
-#define __HAVE_ARCH_STRNLEN     1
-#define __HAVE_ARCH_MEMSET      1
-#define __HAVE_ARCH_MEMCPY      1
-#define __HAVE_ARCH_MEMMOVE     1
-#define __HAVE_ARCH_MEMSCAN     1
-#define __HAVE_ARCH_MEMCMP      1
-#define __HAVE_ARCH_MEMCHR      1
-#define __HAVE_ARCH_STRTOK      1
-
-#endif /* KERNEL */
 #endif /* __ASM_SH_STRING_H */
diff --git a/cmd/config.c b/cmd/config.c
index f0d2033c61f..22115e9b1da 100644
--- a/cmd/config.c
+++ b/cmd/config.c
@@ -6,6 +6,7 @@
 #include <command.h>
 #include <gzip.h>
 #include <malloc.h>
+#include <linux/string.h>
 
 #include "config_data_gz.h"
 #include "config_data_size.h"
@@ -29,7 +30,23 @@ static int do_config(struct cmd_tbl *cmdtp, int flag, int argc,
 	}
 
 	dst[data_size] = 0;
-	puts(dst);
+	if (argc > 1) {
+		const char *s = argv[1];
+		char *b = dst, *e = dst + data_size, *n;
+
+		while (b < e) {
+			n = strchrnul(b, '\n');
+			*n = '\0';
+
+			if (strcasestr(b, s)) {
+				puts(b);
+				puts("\n");
+			}
+			b = n + 1;
+		}
+	} else {
+		puts(dst);
+	}
 
 free:
 	free(dst);
@@ -38,7 +55,10 @@ free:
 }
 
 U_BOOT_CMD(
-	config, 1, 1, do_config,
+	config, 2, 1, do_config,
 	"print .config",
-	""
+	"[str]\n"
+	"\n"
+	"When the optional argument is given, only lines containing\n"
+	"that string are printed. Matching is case-insensitive."
 );
diff --git a/doc/usage/cmd/config.rst b/doc/usage/cmd/config.rst
new file mode 100644
index 00000000000..bd8aa65ddbc
--- /dev/null
+++ b/doc/usage/cmd/config.rst
@@ -0,0 +1,40 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+.. index::
+   single: config (command)
+
+config command
+==============
+
+Synopsis
+--------
+
+::
+
+    config [<str>]
+
+Description
+-----------
+
+The config command prints the `.config` file used when building U-Boot
+to the console. Note that the `.config` file is usually several 1000
+lines long.
+
+If the optional argument is given, only lines containing that string
+(case insensitively) are printed. That can be useful if one wants to
+check whether a specific option is enabled, or just to limit the
+output to the subsystem of interest.
+
+The `.config` file is stored inside the U-Boot binary in
+gzip-compressed format.
+
+Examples
+--------
+
+.. code-block:: bash
+
+    # Print the entire .config
+    config
+
+    # Print all lines related to pinctrl
+    config pinctrl
diff --git a/include/linux/string.h b/include/linux/string.h
index 850356d7c3f..986499dfc70 100644
--- a/include/linux/string.h
+++ b/include/linux/string.h
@@ -43,12 +43,8 @@ extern int strcmp(const char *,const char *);
 #ifndef __HAVE_ARCH_STRNCMP
 extern int strncmp(const char *,const char *,__kernel_size_t);
 #endif
-#ifndef __HAVE_ARCH_STRCASECMP
 int strcasecmp(const char *s1, const char *s2);
-#endif
-#ifndef __HAVE_ARCH_STRNCASECMP
-extern int strncasecmp(const char *s1, const char *s2, __kernel_size_t len);
-#endif
+int strncasecmp(const char *s1, const char *s2, __kernel_size_t len);
 #ifndef __HAVE_ARCH_STRCHR
 extern char * strchr(const char *,int);
 #endif
@@ -63,7 +59,7 @@ extern char * strchr(const char *,int);
  * @c: character to search for
  * Return: position of @c in @s, or end of @s if not found
  */
-const char *strchrnul(const char *s, int c);
+char *strchrnul(const char *s, int c);
 
 #ifndef __HAVE_ARCH_STRRCHR
 extern char * strrchr(const char *,int);
@@ -75,6 +71,7 @@ extern char * strstr(const char *,const char *);
 #ifndef __HAVE_ARCH_STRNSTR
 extern char *strnstr(const char *, const char *, size_t);
 #endif
+char *strcasestr(const char *, const char *);
 #ifndef __HAVE_ARCH_STRLEN
 extern __kernel_size_t strlen(const char *);
 #endif
@@ -107,10 +104,6 @@ extern char * strndup(const char *, size_t);
 extern const char *strdup_const(const char *s);
 extern void kfree_const(const void *x);
 
-#ifndef __HAVE_ARCH_STRSWAB
-extern char * strswab(const char *);
-#endif
-
 #ifndef __HAVE_ARCH_MEMSET
 extern void * memset(void *,int,__kernel_size_t);
 #endif
diff --git a/lib/string.c b/lib/string.c
index 37ea8c29561..dbf2ce340df 100644
--- a/lib/string.c
+++ b/lib/string.c
@@ -263,12 +263,12 @@ char * strchr(const char * s, int c)
 }
 #endif
 
-const char *strchrnul(const char *s, int c)
+char *strchrnul(const char *s, int c)
 {
 	for (; *s != (char)c; ++s)
 		if (*s == '\0')
 			break;
-	return s;
+	return (char *)s;
 }
 
 #ifndef __HAVE_ARCH_STRRCHR
@@ -399,7 +399,6 @@ void kfree_const(const void *x)
 }
 
 
-#ifndef __HAVE_ARCH_STRSPN
 /**
  * strspn - Calculate the length of the initial substring of @s which only
  *	contain letters in @accept
@@ -424,9 +423,7 @@ size_t strspn(const char *s, const char *accept)
 
 	return count;
 }
-#endif
 
-#ifndef __HAVE_ARCH_STRPBRK
 /**
  * strpbrk - Find the first occurrence of a set of characters
  * @cs: The string to be searched
@@ -444,9 +441,7 @@ char * strpbrk(const char * cs,const char * ct)
 	}
 	return NULL;
 }
-#endif
 
-#ifndef __HAVE_ARCH_STRTOK
 /**
  * strtok - Split a string into tokens
  * @s: The string to be searched
@@ -473,9 +468,7 @@ char * strtok(char * s,const char * ct)
 	___strtok = send;
 	return (sbegin);
 }
-#endif
 
-#ifndef __HAVE_ARCH_STRSEP
 /**
  * strsep - Split a string into tokens
  * @s: The string to be searched
@@ -501,35 +494,6 @@ char * strsep(char **s, const char *ct)
 
 	return sbegin;
 }
-#endif
-
-#ifndef __HAVE_ARCH_STRSWAB
-/**
- * strswab - swap adjacent even and odd bytes in %NUL-terminated string
- * s: address of the string
- *
- * returns the address of the swapped string or NULL on error. If
- * string length is odd, last byte is untouched.
- */
-char *strswab(const char *s)
-{
-	char *p, *q;
-
-	if ((NULL == s) || ('\0' == *s)) {
-		return (NULL);
-	}
-
-	for (p=(char *)s, q=p+1; (*p != '\0') && (*q != '\0'); p+=2, q+=2) {
-		char  tmp;
-
-		tmp = *p;
-		*p  = *q;
-		*q  = tmp;
-	}
-
-	return (char *) s;
-}
-#endif
 
 #ifndef __HAVE_ARCH_MEMSET
 /**
@@ -702,7 +666,7 @@ void *memdup(const void *src, size_t len)
  *
  * @s1:		string to be searched
  * @s2:		string to search for
- * @len:	maximum number of characters in s2 to consider
+ * @len:	maximum number of characters in s1 to consider
  *
  * Return:	pointer to the first occurrence or NULL
  */
@@ -728,7 +692,6 @@ char *strnstr(const char *s1, const char *s2, size_t len)
  *
  * @s1:		string to be searched
  * @s2:		string to search for
- * @len:	maximum number of characters in s2 to consider
  *
  * Return:	pointer to the first occurrence or NULL
  */
@@ -738,6 +701,33 @@ char *strstr(const char *s1, const char *s2)
 }
 #endif
 
+/**
+ * strcasestr() - Case insensitive substring search
+ *
+ * @haystack:	string to be searched
+ * @needle:	string to search for
+ *
+ * Return:	pointer to the first occurrence or NULL
+ *
+ * The case of both strings are ignored.
+ */
+char *strcasestr(const char *haystack, const char *needle)
+{
+	size_t l1, l2;
+
+	l1 = strlen(haystack);
+	l2 = strlen(needle);
+
+	while (l1 >= l2) {
+		if (!strncasecmp(haystack, needle, l2))
+			return (char *)haystack;
+		haystack++;
+		l1--;
+	}
+
+	return NULL;
+}
+
 #ifndef __HAVE_ARCH_MEMCHR
 /**
  * memchr - Find a character in an area of memory.
diff --git a/test/cmd/Makefile b/test/cmd/Makefile
index 8d6932f1176..8d36463879d 100644
--- a/test/cmd/Makefile
+++ b/test/cmd/Makefile
@@ -17,6 +17,7 @@ ifdef CONFIG_CONSOLE_RECORD
 obj-$(CONFIG_CMD_ACPI) += acpi.o
 endif
 obj-$(CONFIG_CMD_BDI) += bdinfo.o
+obj-$(CONFIG_CMD_CONFIG) += config.o
 obj-$(CONFIG_COREBOOT_SYSINFO) += coreboot.o
 obj-$(CONFIG_CMD_FDT) += fdt.o
 obj-$(CONFIG_CMD_HASH) += hash.o
diff --git a/test/cmd/config.c b/test/cmd/config.c
new file mode 100644
index 00000000000..5a48060801f
--- /dev/null
+++ b/test/cmd/config.c
@@ -0,0 +1,28 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Tests for config command
+ */
+
+#include <console.h>
+#include <test/cmd.h>
+#include <test/ut.h>
+
+static int cmd_test_config(struct unit_test_state *uts)
+{
+	ut_assertok(run_command("config", 0));
+	ut_assert_skip_to_line("# Automatically generated file; DO NOT EDIT.");
+	ut_assert_skip_to_linen("# Compiler:");
+	ut_assert_skip_to_line("CONFIG_CMD_CONFIG=y");
+
+	console_record_reset_enable();
+
+	ut_assertok(run_command("config cmd_config=y", 0));
+	ut_assert_nextline("CONFIG_CMD_CONFIG=y");
+	ut_assert_console_end();
+
+	ut_assertok(run_command("config 'this string never appears in .config'", 0));
+	ut_assert_console_end();
+
+	return 0;
+}
+CMD_TEST(cmd_test_config, UTF_CONSOLE);
diff --git a/test/lib/string.c b/test/lib/string.c
index db6f28dbfdf..d418a40c4d4 100644
--- a/test/lib/string.c
+++ b/test/lib/string.c
@@ -284,18 +284,36 @@ static int lib_strstr(struct unit_test_state *uts)
 {
 	const char *s1 = "Itsy Bitsy Teenie Weenie";
 	const char *s2 = "eenie";
-	const char *s3 = "easy";
+	const char *s3 = "bits";
 
 	ut_asserteq_ptr(&s1[12], strstr(s1, s2));
 	ut_asserteq_ptr(&s1[13], strstr(&s1[3], &s2[1]));
 	ut_assertnull(strstr(s1, s3));
-	ut_asserteq_ptr(&s1[2], strstr(s1, &s3[2]));
-	ut_asserteq_ptr(&s1[8], strstr(&s1[5], &s3[2]));
+	ut_asserteq_ptr(&s1[1], strstr(s1, &s3[2]));
+	ut_asserteq_ptr(&s1[7], strstr(&s1[5], &s3[2]));
 
 	return 0;
 }
 LIB_TEST(lib_strstr, 0);
 
+/** lib_strcasestr() - unit test for strcasestr() */
+static int lib_strcasestr(struct unit_test_state *uts)
+{
+	const char *s1 = "Itsy Bitsy Teenie Weenie";
+	const char *s2 = "eenie";
+	const char *s3 = "bits";
+
+	ut_asserteq_ptr(&s1[12], strcasestr(s1, s2));
+	ut_asserteq_ptr(&s1[13], strcasestr(&s1[3], &s2[1]));
+	ut_asserteq_ptr(&s1[5], strcasestr(s1, s3));
+	ut_asserteq_ptr(&s1[1], strcasestr(s1, &s3[2]));
+	ut_asserteq_ptr(&s1[7], strcasestr(&s1[5], &s3[2]));
+	ut_assertnull(strcasestr(&s1[6], s3));
+
+	return 0;
+}
+LIB_TEST(lib_strcasestr, 0);
+
 static int lib_strim(struct unit_test_state *uts)
 {
 	char buf[BUFLEN], *p;