1 files changed, 243 insertions, 0 deletions
diff --git a/lib/ngtcp2_vec.c b/lib/ngtcp2_vec.c
new file mode 100644
index 0000000..257332e
--- /dev/null
+++ b/lib/ngtcp2_vec.c
@@ -0,0 +1,243 @@
+/*
+ * ngtcp2
+ *
+ * Copyright (c) 2018 ngtcp2 contributors
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+ * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+ * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+#include "ngtcp2_vec.h"
+
+#include <string.h>
+#include <assert.h>
+
+#include "ngtcp2_str.h"
+
+ngtcp2_vec *ngtcp2_vec_init(ngtcp2_vec *vec, const uint8_t *base, size_t len) {
+  vec->base = (uint8_t *)base;
+  vec->len = len;
+  return vec;
+}
+
+int ngtcp2_vec_new(ngtcp2_vec **pvec, const uint8_t *data, size_t datalen,
+                   const ngtcp2_mem *mem) {
+  size_t len;
+  uint8_t *p;
+
+  len = sizeof(ngtcp2_vec) + datalen;
+
+  *pvec = ngtcp2_mem_malloc(mem, len);
+  if (*pvec == NULL) {
+    return NGTCP2_ERR_NOMEM;
+  }
+
+  p = (uint8_t *)(*pvec) + sizeof(ngtcp2_vec);
+  (*pvec)->base = p;
+  (*pvec)->len = datalen;
+  if (datalen) {
+    /* p = */ ngtcp2_cpymem(p, data, datalen);
+  }
+
+  return 0;
+}
+
+void ngtcp2_vec_del(ngtcp2_vec *vec, const ngtcp2_mem *mem) {
+  ngtcp2_mem_free(mem, vec);
+}
+
+uint64_t ngtcp2_vec_len(const ngtcp2_vec *vec, size_t n) {
+  size_t i;
+  size_t res = 0;
+
+  for (i = 0; i < n; ++i) {
+    res += vec[i].len;
+  }
+
+  return res;
+}
+
+int64_t ngtcp2_vec_len_varint(const ngtcp2_vec *vec, size_t n) {
+  uint64_t res = 0;
+  size_t len;
+  size_t i;
+
+  for (i = 0; i < n; ++i) {
+    len = vec[i].len;
+    if (len > NGTCP2_MAX_VARINT - res) {
+      return -1;
+    }
+
+    res += len;
+  }
+
+  return (int64_t)res;
+}
+
+ngtcp2_ssize ngtcp2_vec_split(ngtcp2_vec *src, size_t *psrccnt, ngtcp2_vec *dst,
+                              size_t *pdstcnt, size_t left, size_t maxcnt) {
+  size_t i;
+  size_t srccnt = *psrccnt;
+  size_t nmove;
+  size_t extra = 0;
+
+  for (i = 0; i < srccnt; ++i) {
+    if (left >= src[i].len) {
+      left -= src[i].len;
+      continue;
+    }
+
+    if (*pdstcnt && src[srccnt - 1].base + src[srccnt - 1].len == dst[0].base) {
+      if (*pdstcnt + srccnt - i - 1 > maxcnt) {
+        return -1;
+      }
+
+      dst[0].len += src[srccnt - 1].len;
+      dst[0].base = src[srccnt - 1].base;
+      extra = src[srccnt - 1].len;
+      --srccnt;
+    } else if (*pdstcnt + srccnt - i > maxcnt) {
+      return -1;
+    }
+
+    if (left == 0) {
+      *psrccnt = i;
+    } else {
+      *psrccnt = i + 1;
+    }
+
+    nmove = srccnt - i;
+    if (nmove) {
+      memmove(dst + nmove, dst, sizeof(ngtcp2_vec) * (*pdstcnt));
+      *pdstcnt += nmove;
+      memcpy(dst, src + i, sizeof(ngtcp2_vec) * nmove);
+    }
+
+    dst[0].len -= left;
+    dst[0].base += left;
+    src[i].len = left;
+
+    if (nmove == 0) {
+      extra -= left;
+    }
+
+    return (ngtcp2_ssize)(ngtcp2_vec_len(dst, nmove) + extra);
+  }
+
+  return 0;
+}
+
+size_t ngtcp2_vec_merge(ngtcp2_vec *dst, size_t *pdstcnt, ngtcp2_vec *src,
+                        size_t *psrccnt, size_t left, size_t maxcnt) {
+  size_t orig_left = left;
+  size_t i;
+  ngtcp2_vec *a, *b;
+
+  assert(maxcnt);
+
+  if (*pdstcnt == 0) {
+    if (*psrccnt == 0) {
+      return 0;
+    }
+
+    a = &dst[0];
+    b = &src[0];
+
+    if (left >= b->len) {
+      *a = *b;
+      ++*pdstcnt;
+      left -= b->len;
+      i = 1;
+    } else {
+      a->len = left;
+      a->base = b->base;
+
+      b->len -= left;
+      b->base += left;
+
+      return left;
+    }
+  } else {
+    i = 0;
+  }
+
+  for (; left && i < *psrccnt; ++i) {
+    a = &dst[*pdstcnt - 1];
+    b = &src[i];
+
+    if (left >= b->len) {
+      if (a->base + a->len == b->base) {
+        a->len += b->len;
+      } else if (*pdstcnt == maxcnt) {
+        break;
+      } else {
+        dst[(*pdstcnt)++] = *b;
+      }
+      left -= b->len;
+      continue;
+    }
+
+    if (a->base + a->len == b->base) {
+      a->len += left;
+    } else if (*pdstcnt == maxcnt) {
+      break;
+    } else {
+      dst[*pdstcnt].len = left;
+      dst[*pdstcnt].base = b->base;
+      ++*pdstcnt;
+    }
+
+    b->len -= left;
+    b->base += left;
+    left = 0;
+
+    break;
+  }
+
+  memmove(src, src + i, sizeof(ngtcp2_vec) * (*psrccnt - i));
+  *psrccnt -= i;
+
+  return orig_left - left;
+}
+
+size_t ngtcp2_vec_copy_at_most(ngtcp2_vec *dst, size_t dstcnt,
+                               const ngtcp2_vec *src, size_t srccnt,
+                               size_t left) {
+  size_t i, j;
+
+  for (i = 0, j = 0; left > 0 && i < srccnt && j < dstcnt;) {
+    if (src[i].len == 0) {
+      ++i;
+      continue;
+    }
+    dst[j] = src[i];
+    if (dst[j].len > left) {
+      dst[j].len = left;
+      return j + 1;
+    }
+    left -= dst[j].len;
+    ++i;
+    ++j;
+  }
+
+  return j;
+}
+
+void ngtcp2_vec_copy(ngtcp2_vec *dst, const ngtcp2_vec *src, size_t cnt) {
+  memcpy(dst, src, sizeof(ngtcp2_vec) * cnt);
+}