Merge branch 'wt/rename' into api-hardening

# Conflicts:
#	README.md

1 files changed, 243 insertions, 0 deletions

diff --git a/include/wsap_vtcore/unicode/utf8.h b/include/wsap_vtcore/unicode/utf8.h
new file mode 100644
index 0000000..7660e41
--- /dev/null
+++ b/include/wsap_vtcore/unicode/utf8.h
@@ -0,0 +1,243 @@
+#ifndef WSAP_VTCORE_UNICODE_UTF8_H
+#define WSAP_VTCORE_UNICODE_UTF8_H
+
+#include <stdint.h>
+#include <stddef.h>
+#include <stdlib.h>
+#include <string.h>
+
+#define WSAP_VTCORE_UTF8_ACCEPT 0
+#define WSAP_VTCORE_UTF8_REJECT 1
+
+#define WSAP_VTCORE_UTF8_3BYTE_MIN 0x800u
+#define WSAP_VTCORE_UTF8_SURROGATE_LO 0xd800u
+#define WSAP_VTCORE_UTF8_SURROGATE_HI 0xdfffu
+
+static const uint8_t wsap_vtcore_utf8d[] = {
+  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
+  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
+  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
+  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
+  1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,
+  7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
+  8,8,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,
+  0xa,0x3,0x3,0x3,0x3,0x3,0x3,0x3,0x3,0x3,0x3,0x3,0x3,0x4,0x3,0x3,
+  0xb,0x6,0x6,0x6,0x5,0x8,0x8,0x8,0x8,0x8,0x8,0x8,0x8,0x8,0x8,0x8,
+  0x0,0x1,0x2,0x3,0x5,0x8,0x7,0x1,0x1,0x1,0x4,0x6,0x1,0x1,0x1,0x1,
+  1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,0,1,1,1,1,1,0,1,0,1,1,1,1,1,1,
+  1,2,1,1,1,1,1,2,1,2,1,1,1,1,1,1,1,1,1,1,1,1,1,2,1,1,1,1,1,1,1,1,
+  1,2,1,1,1,1,1,1,1,2,1,1,1,1,1,1,1,1,1,1,1,1,1,3,1,3,1,1,1,1,1,1,
+  1,3,1,1,1,1,1,3,1,3,1,1,1,1,1,1,1,3,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
+};
+
+static inline uint32_t wsap_vtcore_utf8_decode(uint32_t *state, uint32_t *codep, uint32_t byte) {
+  byte &= 0xff;
+  uint32_t type = wsap_vtcore_utf8d[byte];
+
+  *codep = (*state != WSAP_VTCORE_UTF8_ACCEPT) ?
+    (byte & 0x3fu) | (*codep << 6) :
+    (0xff >> type) & (byte);
+
+  *state = wsap_vtcore_utf8d[256 + *state*16 + type];
+  return *state;
+}
+
+static const uint8_t wsap_vtcore_utf8_acc_state[256] = {
+0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
+2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
+4, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 5, 3, 3,
+6, 7, 7, 7, 8, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+};
+static const uint8_t wsap_vtcore_utf8_acc_codep[256] = {
+0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,
+16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31,
+32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47,
+48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63,
+64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79,
+80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95,
+96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111,
+112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127,
+0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,
+0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1,
+0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1,
+0, 0, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,
+16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31,
+0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,
+0, 1, 2, 3, 4, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+};
+
+/*
+ * Decode one code point at the start of buf and return the bytes it used.
+ * Each maximal invalid subpart gives U+FFFD (Unicode 3.9); the byte that
+ * ends a subpart stays unused, so the caller reads it again. A C0 control
+ * ends an unfinished sequence the same way. An unfinished sequence at the
+ * end of buf gives *cp = 0 and keeps the state.
+ */
+static inline int wsap_vtcore_utf8_decode_ground(uint32_t *state, uint32_t *codep,
+                                     const char *buf, size_t len, uint32_t *cp) {
+    uint32_t st = *state;
+    uint32_t cpv = *codep;
+    int n = 0;
+    *cp = 0;
+    if (len == 0)
+        return 0;
+    do {
+        unsigned char c = (unsigned char)buf[n];
+        if (c < 0x20) {
+            if (st != WSAP_VTCORE_UTF8_ACCEPT) *cp = 0xFFFD;
+            st = WSAP_VTCORE_UTF8_ACCEPT;
+            break;
+        }
+        uint32_t before = st;
+        n++;
+        if (st == WSAP_VTCORE_UTF8_ACCEPT) {
+            cpv = wsap_vtcore_utf8_acc_codep[c];
+            st = wsap_vtcore_utf8_acc_state[c];
+        } else {
+            uint32_t type = wsap_vtcore_utf8d[c];
+            cpv = (c & 0x3fu) | (cpv << 6);
+            st = wsap_vtcore_utf8d[256 + st*16 + type];
+        }
+        if (st == WSAP_VTCORE_UTF8_ACCEPT) { *cp = cpv; break; }
+        if (st == WSAP_VTCORE_UTF8_REJECT) {
+            st = WSAP_VTCORE_UTF8_ACCEPT;
+            *cp = 0xFFFD;
+            if (before != WSAP_VTCORE_UTF8_ACCEPT) n--;
+            break;
+        }
+    } while ((size_t)n < len);
+    *state = st;
+    *codep = cpv;
+    return n;
+}
+
+static inline int
+wsap_vtcore_utf8_decode_one(const char *buf, size_t len, uint32_t *codep)
+{
+    const unsigned char *s = (const unsigned char *)buf;
+    unsigned c0, c1, c2, c3;
+    uint32_t cp;
+
+    if (len == 0)
+        return 0;
+    c0 = s[0];
+    if (c0 < 0x80) {
+        *codep = c0;
+        return 1;
+    }
+    if (c0 < 0xc2 || c0 > 0xf4)
+        return 0;
+
+    if (c0 <= 0xdf) {
+        if (len < 2)
+            return 0;
+        c1 = s[1];
+        if ((c1 & 0xc0) != 0x80)
+            return 0;
+        *codep = ((c0 & 0x1f) << 6) | (c1 & 0x3f);
+        return 2;
+    }
+
+    if (c0 <= 0xef) {
+        if (len < 3)
+            return 0;
+        c1 = s[1];
+        c2 = s[2];
+        if ((c1 & 0xc0) != 0x80 || (c2 & 0xc0) != 0x80)
+            return 0;
+        cp = ((c0 & 0x0f) << 12) | ((c1 & 0x3f) << 6) | (c2 & 0x3f);
+        if (cp < WSAP_VTCORE_UTF8_3BYTE_MIN ||
+            (cp >= WSAP_VTCORE_UTF8_SURROGATE_LO && cp <= WSAP_VTCORE_UTF8_SURROGATE_HI))
+            return 0;
+        *codep = cp;
+        return 3;
+    }
+
+    if (len < 4)
+        return 0;
+    c1 = s[1];
+    c2 = s[2];
+    c3 = s[3];
+    if ((c1 & 0xc0) != 0x80 || (c2 & 0xc0) != 0x80 ||
+        (c3 & 0xc0) != 0x80)
+        return 0;
+    cp = ((c0 & 0x07) << 18) | ((c1 & 0x3f) << 12) |
+         ((c2 & 0x3f) << 6) | (c3 & 0x3f);
+    if (cp < 0x10000 || cp > 0x10ffff)
+        return 0;
+    *codep = cp;
+    return 4;
+}
+
+static inline void
+wsap_vtcore_utf8_sanitize(char *dst, size_t cap, const char *src)
+{
+    if (!cap)
+        return;
+    size_t i = 0, len = strlen(src), off = 0;
+    while (off < len && i + 1 < cap) {
+        uint32_t cp;
+        int n = wsap_vtcore_utf8_decode_one(src + off, len - off, &cp);
+        if (n <= 0 || i + (size_t)n >= cap) {
+            off++;
+            continue;
+        }
+        memcpy(dst + i, src + off, (size_t)n);
+        i += (size_t)n;
+        off += (size_t)n;
+    }
+    dst[i] = '\0';
+}
+
+/* A sanitized copy of src. Sanitizing only drops bytes, so the copy is
+ * never longer than src. */
+static inline char *wsap_vtcore_utf8_sanitize_dup(const char *src)
+{
+    size_t cap = strlen(src) + 1;
+    char *dst = (char *)malloc(cap);
+    if (dst)
+        wsap_vtcore_utf8_sanitize(dst, cap, src);
+    return dst;
+}
+
+#define WSAP_VTCORE_UTF8_MAX_BYTES 4
+static inline int wsap_vtcore_utf8_encode(uint32_t cp, char *out)
+{
+    if (cp > 0x10ffff || (cp >= 0xd800 && cp <= 0xdfff))
+        cp = 0xfffd;
+    if (cp < 0x80) {
+        out[0] = (char)cp;
+        return 1;
+    }
+    if (cp < 0x800) {
+        out[0] = (char)(0xc0 | (cp >> 6));
+        out[1] = (char)(0x80 | (cp & 0x3f));
+        return 2;
+    }
+    if (cp < 0x10000) {
+        out[0] = (char)(0xe0 | (cp >> 12));
+        out[1] = (char)(0x80 | ((cp >> 6) & 0x3f));
+        out[2] = (char)(0x80 | (cp & 0x3f));
+        return 3;
+    }
+    out[0] = (char)(0xf0 | (cp >> 18));
+    out[1] = (char)(0x80 | ((cp >> 12) & 0x3f));
+    out[2] = (char)(0x80 | ((cp >> 6) & 0x3f));
+    out[3] = (char)(0x80 | (cp & 0x3f));
+    return 4;
+}
+
+#endif