string[1/2]: added more string manipulation functions.

strpbrk, strstr, strsep, strcasecmp, strncasecmp. fixed return type of snprintf. Signed-off-by: Deepak Gupta <[email protected]>
KernelTestFramework · Sep 4, 2020 · dd61a7a · dd61a7a
1 parent 280e9fb
commit dd61a7a
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Showing 2 changed files with 132 additions and 3 deletions.
diff --git a/include/string.h b/include/string.h
@@ -25,6 +25,7 @@
 #ifndef KTF_STRING_H
 #define KTF_STRING_H
 #include <asm-macros.h>
+#include <slab.h>
 
 static inline __used int isspace(int c) { return c == ' ' || c == '\t'; }
 
@@ -182,6 +183,21 @@ static inline int strcmp(const char *s1, const char *s2) {
     return res;
 }
 
+static inline char *strncpy(char *d, const char *s, size_t n) {
+    char *copy = d;
+
+    while (n) {
+        *copy++ = *s++;
+        if (*s == '\0')
+            break;
+        n--;
+    }
+
+    memset(copy, '\0', n);
+
+    return d;
+}
+
 static inline char *strchr(const char *s, int c) {
     if (NULL == s)
         return NULL;
@@ -222,11 +238,121 @@ static inline int string_equal(const char *s1, const char *s2) {
     return (!s1 || !s2) ? s1 == s2 : !strcmp(s1, s2);
 }
 
+static inline char *strpbrk(const char *s, const char *chars) {
+    for (int i = 0; s[i] != '\0'; i++) {
+        for (int j = 0; chars[j] != '\0'; j++) {
+            if (s[i] == chars[j]) {
+                return (char *) &s[i];
+            }
+        }
+    }
+
+    return NULL;
+}
+
+static inline char *strstr(const char *s1, const char *s2) {
+    char *a = NULL, *b = NULL;
+
+    b = (char *) s2;
+    /* s2 is NULL terminated, return entire s1 */
+    if ('\0' == *b) {
+        return (char *) s1;
+    }
+
+    /* first char match in s1 */
+    for (; *s1 != '\0'; s1++) {
+        if (*s1 != *b) {
+            continue;
+        }
+        /* record the position */
+        a = (char *) s1;
+
+        while (1) {
+            /* s2 has been searched, return s1 */
+            if (*b == '\0') {
+                return (char *) s1;
+            }
+            /* no match, break and find new a */
+            if (*a++ != *b++) {
+                break;
+            }
+        }
+        /* rewind b all the way back to s2 start */
+        b = (char *) s2;
+    }
+
+    return NULL;
+}
+
+static inline char *strsep(char **str, char *delim) {
+    char *spanp = NULL, *s = NULL;
+    int c, sc;
+    char *tok = NULL;
+
+    s = *str;
+    if (NULL == s)
+        return NULL;
+
+    for (tok = s;; ++s) {
+        c = *s;
+        spanp = delim;
+        do {
+            if ((sc = *spanp++) == c) {
+                if (c == '\0') {
+                    *str = NULL;
+                    return (tok == s ? NULL : tok);
+                }
+                *s++ = '\0';
+                *str = s;
+                return tok;
+            }
+        } while (sc);
+    }
+}
+
+static inline int strcasecmp(const char *s1, const char *s2) {
+    unsigned char res, c1, c2;
+
+    if (s1 == s2)
+        return 0;
+
+    while (1) {
+        c1 = tolower(*(unsigned char *) s1);
+        s1++;
+        c2 = tolower(*(unsigned char *) s2);
+        s2++;
+        res = c1 - c2;
+        if ((res != 0 || c1 == 0 || c2 == 0))
+            break;
+    }
+
+    return res;
+}
+
+static inline int strncasecmp(const char *s1, const char *s2, size_t n) {
+    unsigned char res = 0, c1, c2;
+
+    if (s1 == s2)
+        return 0;
+
+    while (n--) {
+        c1 = tolower(*(unsigned char *) s1);
+        s1++;
+        c2 = tolower(*(unsigned char *) s2);
+        s2++;
+        res = c1 - c2;
+        if (res != 0 || c1 == 0 || c2 == 0)
+            break;
+    }
+
+    return res;
+}
+
 /* External declarations */
 
 extern unsigned long strtoul(const char *nptr, char **endptr, int base);
 extern long strtol(const char *nptr, char **endptr, int base);
 extern int vsnprintf(char *str, size_t size, char const *fmt, va_list ap);
-extern void snprintf(char *buf, size_t size, const char *fmt, ...);
+extern int snprintf(char *buf, size_t size, const char *fmt, ...);
 
 #endif /* KTF_STRING_H */
diff --git a/lib/string.c b/lib/string.c
@@ -495,11 +495,14 @@ reswitch:       switch (ch = (unsigned char)*fmt++) {
 #undef PCHAR
 }
 
-void snprintf(char *buf, size_t size, const char *fmt, ...) {
+int snprintf(char *buf, size_t size, const char *fmt, ...) {
     va_list args;
+    int retval = 0;
 
     va_start(args, fmt);
-    vsnprintf(buf, size, fmt, args);
+    retval = vsnprintf(buf, size, fmt, args);
     va_end(args);
+
+    return retval;
 }
 /* clang-format on */