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-rw-r--r--lib/ccan/str/str.h200
1 files changed, 200 insertions, 0 deletions
diff --git a/lib/ccan/str/str.h b/lib/ccan/str/str.h
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+++ b/lib/ccan/str/str.h
@@ -0,0 +1,200 @@
+#ifndef CCAN_STR_H
+#define CCAN_STR_H
+#include "config.h"
+#include <string.h>
+#include <stdbool.h>
+#include <ctype.h>
+
+/**
+ * streq - Are two strings equal?
+ * @a: first string
+ * @b: first string
+ *
+ * This macro is arguably more readable than "!strcmp(a, b)".
+ *
+ * Example:
+ * if (streq(somestring, ""))
+ * printf("String is empty!\n");
+ */
+#define streq(a,b) (strcmp((a),(b)) == 0)
+
+/**
+ * strstarts - Does this string start with this prefix?
+ * @str: string to test
+ * @prefix: prefix to look for at start of str
+ *
+ * Example:
+ * if (strstarts(somestring, "foo"))
+ * printf("String %s begins with 'foo'!\n", somestring);
+ */
+#define strstarts(str,prefix) (strncmp((str),(prefix),strlen(prefix)) == 0)
+
+/**
+ * strends - Does this string end with this postfix?
+ * @str: string to test
+ * @postfix: postfix to look for at end of str
+ *
+ * Example:
+ * if (strends(somestring, "foo"))
+ * printf("String %s end with 'foo'!\n", somestring);
+ */
+static inline bool strends(const char *str, const char *postfix)
+{
+ if (strlen(str) < strlen(postfix))
+ return false;
+
+ return streq(str + strlen(str) - strlen(postfix), postfix);
+}
+
+/**
+ * stringify - Turn expression into a string literal
+ * @expr: any C expression
+ *
+ * Example:
+ * #define PRINT_COND_IF_FALSE(cond) \
+ * ((cond) || printf("%s is false!", stringify(cond)))
+ */
+#define stringify(expr) stringify_1(expr)
+/* Double-indirection required to stringify expansions */
+#define stringify_1(expr) #expr
+
+/**
+ * strcount - Count number of (non-overlapping) occurrences of a substring.
+ * @haystack: a C string
+ * @needle: a substring
+ *
+ * Example:
+ * int i;
+ * i = strcount("aaa aaa", "a"); // i = 6;
+ * i = strcount("aaa aaa", "ab"); // i = 0;
+ * i = strcount("aaa aaa", "aa"); // i = 2;
+ */
+size_t strcount(const char *haystack, const char *needle);
+
+/**
+ * cisalnum - isalnum() which takes a char (and doesn't accept EOF)
+ * @c: a character
+ *
+ * Surprisingly, the standard ctype.h isalnum() takes an int, which
+ * must have the value of EOF (-1) or an unsigned char. This variant
+ * takes a real char, and doesn't accept EOF.
+ */
+static inline bool cisalnum(char c)
+{
+ return isalnum((unsigned char)c);
+}
+static inline bool cisalpha(char c)
+{
+ return isalpha((unsigned char)c);
+}
+static inline bool cisascii(char c)
+{
+ return isascii((unsigned char)c);
+}
+#if HAVE_ISBLANK
+static inline bool cisblank(char c)
+{
+ return isblank((unsigned char)c);
+}
+#endif
+static inline bool ciscntrl(char c)
+{
+ return iscntrl((unsigned char)c);
+}
+static inline bool cisdigit(char c)
+{
+ return isdigit((unsigned char)c);
+}
+static inline bool cisgraph(char c)
+{
+ return isgraph((unsigned char)c);
+}
+static inline bool cislower(char c)
+{
+ return islower((unsigned char)c);
+}
+static inline bool cisprint(char c)
+{
+ return isprint((unsigned char)c);
+}
+static inline bool cispunct(char c)
+{
+ return ispunct((unsigned char)c);
+}
+static inline bool cisspace(char c)
+{
+ return isspace((unsigned char)c);
+}
+static inline bool cisupper(char c)
+{
+ return isupper((unsigned char)c);
+}
+static inline bool cisxdigit(char c)
+{
+ return isxdigit((unsigned char)c);
+}
+
+#include <ccan/str/str_debug.h>
+
+/* These checks force things out of line, hence they are under DEBUG. */
+#ifdef CCAN_STR_DEBUG
+#include <ccan/build_assert/build_assert.h>
+
+/* These are commonly misused: they take -1 or an *unsigned* char value. */
+#undef isalnum
+#undef isalpha
+#undef isascii
+#undef isblank
+#undef iscntrl
+#undef isdigit
+#undef isgraph
+#undef islower
+#undef isprint
+#undef ispunct
+#undef isspace
+#undef isupper
+#undef isxdigit
+
+/* You can use a char if char is unsigned. */
+#if HAVE_BUILTIN_TYPES_COMPATIBLE_P && HAVE_TYPEOF
+#define str_check_arg_(i) \
+ ((i) + BUILD_ASSERT_OR_ZERO(!__builtin_types_compatible_p(typeof(i), \
+ char) \
+ || (char)255 > 0))
+#else
+#define str_check_arg_(i) (i)
+#endif
+
+#define isalnum(i) str_isalnum(str_check_arg_(i))
+#define isalpha(i) str_isalpha(str_check_arg_(i))
+#define isascii(i) str_isascii(str_check_arg_(i))
+#if HAVE_ISBLANK
+#define isblank(i) str_isblank(str_check_arg_(i))
+#endif
+#define iscntrl(i) str_iscntrl(str_check_arg_(i))
+#define isdigit(i) str_isdigit(str_check_arg_(i))
+#define isgraph(i) str_isgraph(str_check_arg_(i))
+#define islower(i) str_islower(str_check_arg_(i))
+#define isprint(i) str_isprint(str_check_arg_(i))
+#define ispunct(i) str_ispunct(str_check_arg_(i))
+#define isspace(i) str_isspace(str_check_arg_(i))
+#define isupper(i) str_isupper(str_check_arg_(i))
+#define isxdigit(i) str_isxdigit(str_check_arg_(i))
+
+#if HAVE_TYPEOF
+/* With GNU magic, we can make const-respecting standard string functions. */
+#undef strstr
+#undef strchr
+#undef strrchr
+
+/* + 0 is needed to decay array into pointer. */
+#define strstr(haystack, needle) \
+ ((typeof((haystack) + 0))str_strstr((haystack), (needle)))
+#define strchr(haystack, c) \
+ ((typeof((haystack) + 0))str_strchr((haystack), (c)))
+#define strrchr(haystack, c) \
+ ((typeof((haystack) + 0))str_strrchr((haystack), (c)))
+#endif
+#endif /* CCAN_STR_DEBUG */
+
+#endif /* CCAN_STR_H */