Initial version.

src/nxt_string.c

@@ -0,0 +1,317 @@
+
+/*
+ * Copyright (C) Igor Sysoev
+ * Copyright (C) NGINX, Inc.
+ */
+
+#include <nxt_main.h>
+
+
+nxt_str_t *
+nxt_str_alloc(nxt_mem_pool_t *mp, size_t len)
+{
+    nxt_str_t  *s;
+
+    /* The string data is allocated aligned to be close to nxt_str_t. */
+    s = nxt_mem_alloc(mp, sizeof(nxt_str_t) + len);
+
+    if (nxt_fast_path(s != NULL)) {
+        s->len = len;
+        s->data = (u_char *) s + sizeof(nxt_str_t);
+    }
+
+    return s;
+}
+
+
+/*
+ * nxt_str_dup() creates a new string with a copy of a source string.
+ * If length of the source string is zero, then the new string anyway
+ * gets a pointer somewhere in mem_pool.
+ */
+
+nxt_str_t *
+nxt_str_dup(nxt_mem_pool_t *mp, nxt_str_t *dst, const nxt_str_t *src)
+{
+    u_char  *p;
+
+    if (dst == NULL) {
+        /* The string data is allocated aligned to be close to nxt_str_t. */
+        dst = nxt_mem_alloc(mp, sizeof(nxt_str_t) + src->len);
+        if (nxt_slow_path(dst == NULL)) {
+            return NULL;
+        }
+
+        p = (u_char *) dst;
+        p += sizeof(nxt_str_t);
+        dst->data = p;
+
+    } else {
+        dst->data = nxt_mem_nalloc(mp, src->len);
+        if (nxt_slow_path(dst->data == NULL)) {
+            return NULL;
+        }
+    }
+
+    nxt_memcpy(dst->data, src->data, src->len);
+    dst->len = src->len;
+
+    return dst;
+}
+
+
+/*
+ * nxt_str_copy() creates a C style zero-terminated copy of a source
+ * nxt_str_t.  The function is intended to create strings suitable
+ * for libc and kernel interfaces so result is pointer to char instead
+ * of u_char to minimize casts.  The copy is aligned to 2 bytes thus
+ * the lowest bit may be used as marker.
+ */
+
+char *
+nxt_str_copy(nxt_mem_pool_t *mp, const nxt_str_t *src)
+{
+    char  *p, *dst;
+
+    dst = nxt_mem_align(mp, 2, src->len + 1);
+
+    if (nxt_fast_path(dst != NULL)) {
+        p = nxt_cpymem(dst, src->data, src->len);
+        *p = '\0';
+    }
+
+    return dst;
+}
+
+
+void
+nxt_memcpy_lowcase(u_char *dst, const u_char *src, size_t len)
+{
+    u_char  c;
+
+    while (len != 0) {
+        c = *src++;
+        *dst++ = nxt_lowcase(c);
+        len--;
+    }
+}
+
+
+u_char *
+nxt_cpystrn(u_char *dst, const u_char *src, size_t len)
+{
+    if (len == 0) {
+        return dst;
+    }
+
+    while (--len != 0) {
+        *dst = *src;
+
+        if (*dst == '\0') {
+            return dst;
+        }
+
+        dst++;
+        src++;
+    }
+
+    *dst = '\0';
+
+    return dst;
+}
+
+
+nxt_int_t
+nxt_strcasecmp(const u_char *s1, const u_char *s2)
+{
+    u_char     c1, c2;
+    nxt_int_t  n;
+
+    for ( ;; ) {
+        c1 = *s1++;
+        c2 = *s2++;
+
+        c1 = nxt_lowcase(c1);
+        c2 = nxt_lowcase(c2);
+
+        n = c1 - c2;
+
+        if (n != 0) {
+            return n;
+        }
+
+        if (c1 == 0) {
+            return 0;
+        }
+    }
+}
+
+
+nxt_int_t
+nxt_strncasecmp(const u_char *s1, const u_char *s2, size_t len)
+{
+    u_char     c1, c2;
+    nxt_int_t  n;
+
+    while (len-- != 0) {
+        c1 = *s1++;
+        c2 = *s2++;
+
+        c1 = nxt_lowcase(c1);
+        c2 = nxt_lowcase(c2);
+
+        n = c1 - c2;
+
+        if (n != 0) {
+            return n;
+        }
+
+        if (c1 == 0) {
+            return 0;
+        }
+    }
+
+    return 0;
+}
+
+
+nxt_int_t
+nxt_memcasecmp(const u_char *s1, const u_char *s2, size_t len)
+{
+    u_char     c1, c2;
+    nxt_int_t  n;
+
+    while (len-- != 0) {
+        c1 = *s1++;
+        c2 = *s2++;
+
+        c1 = nxt_lowcase(c1);
+        c2 = nxt_lowcase(c2);
+
+        n = c1 - c2;
+
+        if (n != 0) {
+            return n;
+        }
+    }
+
+    return 0;
+}
+
+
+/*
+ * nxt_memstrn() is intended for search of static substring "ss"
+ * with known length "len" in string "s" limited by parameter "end".
+ * Zeros are ignored in both strings.
+ */
+
+u_char *
+nxt_memstrn(const u_char *s, const u_char *end, const char *ss, size_t len)
+{
+    u_char  c1, c2, *s2;
+
+    s2 = (u_char *) ss;
+    c2 = *s2++;
+    len--;
+
+    while (s < end) {
+        c1 = *s++;
+
+        if (c1 == c2) {
+
+            if (s + len > end) {
+                return NULL;
+            }
+
+            if (nxt_memcmp(s, s2, len) == 0) {
+                return (u_char *) s - 1;
+            }
+        }
+    }
+
+    return NULL;
+}
+
+
+/*
+ * nxt_strcasestrn() is intended for caseless search of static substring
+ * "ss" with known length "len" in string "s" limited by parameter "end".
+ * Zeros are ignored in both strings.
+ */
+
+u_char *
+nxt_memcasestrn(const u_char *s, const u_char *end, const char *ss, size_t len)
+{
+    u_char  c1, c2, *s2;
+
+    s2 = (u_char *) ss;
+    c2 = *s2++;
+    c2 = nxt_lowcase(c2);
+    len--;
+
+    while (s < end) {
+        c1 = *s++;
+        c1 = nxt_lowcase(c1);
+
+        if (c1 == c2) {
+
+            if (s + len > end) {
+                return NULL;
+            }
+
+            if (nxt_memcasecmp(s, s2, len) == 0) {
+                return (u_char *) s - 1;
+            }
+        }
+    }
+
+    return NULL;
+}
+
+
+/*
+ * nxt_rstrstrn() is intended to search for static substring "ss"
+ * with known length "len" in string "s" limited by parameter "end"
+ * in reverse order.  Zeros are ignored in both strings.
+ */
+
+u_char *
+nxt_rmemstrn(const u_char *s, const u_char *end, const char *ss, size_t len)
+{
+    u_char        c1, c2;
+    const u_char  *s1, *s2;
+
+    s1 = end - len;
+    s2 = (u_char *) ss;
+    c2 = *s2++;
+    len--;
+
+    while (s < s1) {
+        c1 = *s1;
+
+        if (c1 == c2) {
+            if (nxt_memcmp(s1 + 1, s2, len) == 0) {
+                return (u_char *) s1;
+            }
+        }
+
+        s1--;
+    }
+
+    return NULL;
+}
+
+
+size_t
+nxt_str_strip(u_char *start, u_char *end)
+{
+    u_char  *p;
+
+    for (p = end - 1; p >= start; p--) {
+        if (*p != NXT_CR && *p != NXT_LF) {
+            break;
+        }
+    }
+
+    return (p + 1) - start;
+}