Merge remote-tracking branch 'upstream/master' into floattitlefloattitle

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diff --git a/src/klib/khash.h b/src/klib/khash.h
new file mode 100644
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--- /dev/null
+++ b/src/klib/khash.h
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+/* The MIT License
+
+   Copyright (c) 2008, 2009, 2011 by Attractive Chaos <attractor@live.co.uk>
+
+   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.
+ */
+
+/*
+   Example:
+
+ #include "nvim/khash.h"
+   KHASH_MAP_INIT_INT(32, char)
+   int main() {
+    int ret, is_missing;
+    khiter_t k;
+    khash_t(32) *h = kh_init(32);
+    k = kh_put(32, h, 5, &ret);
+    kh_value(h, k) = 10;
+    k = kh_get(32, h, 10);
+    is_missing = (k == kh_end(h));
+    k = kh_get(32, h, 5);
+    kh_del(32, h, k);
+    for (k = kh_begin(h); k != kh_end(h); ++k)
+        if (kh_exist(h, k)) kh_value(h, k) = 1;
+    kh_destroy(32, h);
+    return 0;
+   }
+ */
+
+/*
+   2013-05-02 (0.2.8):
+
+ * Use quadratic probing. When the capacity is power of 2, stepping function
+          i*(i+1)/2 guarantees to traverse each bucket. It is better than double
+          hashing on cache performance and is more robust than linear probing.
+
+          In theory, double hashing should be more robust than quadratic probing.
+          However, my implementation is probably not for large hash tables, because
+          the second hash function is closely tied to the first hash function,
+          which reduce the effectiveness of double hashing.
+
+        Reference: http://research.cs.vt.edu/AVresearch/hashing/quadratic.php
+
+   2011-12-29 (0.2.7):
+
+ * Minor code clean up; no actual effect.
+
+   2011-09-16 (0.2.6):
+
+ * The capacity is a power of 2. This seems to dramatically improve the
+          speed for simple keys. Thank Zilong Tan for the suggestion. Reference:
+
+           - http://code.google.com/p/ulib/
+           - http://nothings.org/computer/judy/
+
+ * Allow to optionally use linear probing which usually has better
+          performance for random input. Double hashing is still the default as it
+          is more robust to certain non-random input.
+
+ * Added Wang's integer hash function (not used by default). This hash
+          function is more robust to certain non-random input.
+
+   2011-02-14 (0.2.5):
+
+ * Allow to declare global functions.
+
+   2009-09-26 (0.2.4):
+
+ * Improve portability
+
+   2008-09-19 (0.2.3):
+
+ * Corrected the example
+ * Improved interfaces
+
+   2008-09-11 (0.2.2):
+
+ * Improved speed a little in kh_put()
+
+   2008-09-10 (0.2.1):
+
+ * Added kh_clear()
+ * Fixed a compiling error
+
+   2008-09-02 (0.2.0):
+
+ * Changed to token concatenation which increases flexibility.
+
+   2008-08-31 (0.1.2):
+
+ * Fixed a bug in kh_get(), which has not been tested previously.
+
+   2008-08-31 (0.1.1):
+
+ * Added destructor
+ */
+
+#ifndef NVIM_LIB_KHASH_H
+#define NVIM_LIB_KHASH_H
+
+/*!
+   @header
+
+   Generic hash table library.
+ */
+
+#define AC_VERSION_KHASH_H "0.2.8"
+
+#include <limits.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "nvim/func_attr.h"
+#include "nvim/memory.h"
+
+// compiler specific configuration
+
+#if UINT_MAX == 0xffffffffu
+typedef unsigned int khint32_t;
+#elif ULONG_MAX == 0xffffffffu
+typedef unsigned long khint32_t;
+#endif
+
+#if ULONG_MAX == ULLONG_MAX
+typedef unsigned long khint64_t;
+#else
+typedef unsigned long long khint64_t;
+#endif
+
+#ifdef _MSC_VER
+# define kh_inline __inline
+#else
+# define kh_inline inline
+#endif
+
+typedef khint32_t khint_t;
+typedef khint_t khiter_t;
+
+#define __ac_isempty(flag, i) ((flag[i>>4]>>((i&0xfU)<<1))&2)
+#define __ac_isdel(flag, i) ((flag[i>>4]>>((i&0xfU)<<1))&1)
+#define __ac_iseither(flag, i) ((flag[i>>4]>>((i&0xfU)<<1))&3)
+#define __ac_set_isdel_false(flag, i) (flag[i>>4]&=~(khint_t)(1ul<<((i&0xfU)<<1)))
+#define __ac_set_isempty_false(flag, i) (flag[i>>4]&=~(khint_t)(2ul<<((i&0xfU)<<1)))
+#define __ac_set_isboth_false(flag, i) (flag[i>>4]&=~(khint_t)(3ul<<((i&0xfU)<<1)))
+#define __ac_set_isdel_true(flag, i) (flag[i>>4]|=(khint_t)1ul<<((i&0xfU)<<1))
+
+#define __ac_fsize(m) ((m) < 16? 1 : (m)>>4)
+
+#ifndef kroundup32
+# define kroundup32(x) (--(x), (x)|=(x)>>1, (x)|=(x)>>2, (x)|=(x)>>4, (x)|=(x)>>8, (x)|=(x)>>16, \
+                        ++(x))
+#endif
+
+#ifndef kcalloc
+# define kcalloc(N, Z) xcalloc(N, Z)
+#endif
+#ifndef kmalloc
+# define kmalloc(Z) xmalloc(Z)
+#endif
+#ifndef krealloc
+# define krealloc(P, Z) xrealloc(P, Z)
+#endif
+#ifndef kfree
+# define kfree(P) XFREE_CLEAR(P)
+#endif
+
+#define __ac_HASH_UPPER 0.77
+
+#define __KHASH_TYPE(name, khkey_t, khval_t) \
+  typedef struct { \
+    khint_t n_buckets, size, n_occupied, upper_bound; \
+    khint32_t *flags; \
+    khkey_t *keys; \
+    khval_t *vals; \
+  } kh_##name##_t;
+
+#define __KHASH_PROTOTYPES(name, khkey_t, khval_t) \
+  extern kh_##name##_t *kh_init_##name(void); \
+  extern void kh_dealloc_##name(kh_##name##_t *h); \
+  extern void kh_destroy_##name(kh_##name##_t *h); \
+  extern void kh_clear_##name(kh_##name##_t *h); \
+  extern khint_t kh_get_##name(const kh_##name##_t *h, khkey_t key); \
+  extern void kh_resize_##name(kh_##name##_t *h, khint_t new_n_buckets); \
+  extern khint_t kh_put_##name(kh_##name##_t *h, khkey_t key, int *ret); \
+  extern void kh_del_##name(kh_##name##_t *h, khint_t x);
+
+#define __KHASH_IMPL(name, SCOPE, khkey_t, khval_t, kh_is_map, __hash_func, \
+                     __hash_equal) \
+  SCOPE kh_##name##_t *kh_init_##name(void) \
+  REAL_FATTR_UNUSED; \
+  SCOPE kh_##name##_t *kh_init_##name(void) { \
+    return (kh_##name##_t *)kcalloc(1, sizeof(kh_##name##_t)); \
+  } \
+  SCOPE void kh_dealloc_##name(kh_##name##_t *h) \
+  REAL_FATTR_UNUSED; \
+  SCOPE void kh_dealloc_##name(kh_##name##_t *h) \
+  { \
+    kfree(h->keys); \
+    kfree(h->flags); \
+    kfree(h->vals); \
+  } \
+  SCOPE void kh_destroy_##name(kh_##name##_t *h) \
+  REAL_FATTR_UNUSED; \
+  SCOPE void kh_destroy_##name(kh_##name##_t *h) \
+  { \
+    if (h) { \
+      kh_dealloc_##name(h); \
+      kfree(h); \
+    } \
+  } \
+  SCOPE void kh_clear_##name(kh_##name##_t *h) \
+  REAL_FATTR_UNUSED; \
+  SCOPE void kh_clear_##name(kh_##name##_t *h) \
+  { \
+    if (h && h->flags) { \
+      memset(h->flags, 0xaa, __ac_fsize(h->n_buckets) * sizeof(khint32_t)); \
+      h->size = h->n_occupied = 0; \
+    } \
+  } \
+  SCOPE khint_t kh_get_##name(const kh_##name##_t *h, khkey_t key) \
+  REAL_FATTR_UNUSED; \
+  SCOPE khint_t kh_get_##name(const kh_##name##_t *h, khkey_t key) \
+  { \
+    if (h->n_buckets) { \
+      khint_t k, i, last, mask, step = 0; \
+      mask = h->n_buckets - 1; \
+      k = __hash_func(key); i = k & mask; \
+      last = i; \
+      while (!__ac_isempty(h->flags, i) && (__ac_isdel(h->flags, i) || \
+                                            !__hash_equal(h->keys[i], key))) { \
+        i = (i + (++step)) & mask; \
+        if (i == last) { \
+          return h->n_buckets; \
+        } \
+      } \
+      return __ac_iseither(h->flags, i) ? h->n_buckets : i; \
+    } else { \
+      return 0; \
+    } \
+  } \
+  SCOPE void kh_resize_##name(kh_##name##_t *h, khint_t new_n_buckets) \
+  REAL_FATTR_UNUSED; \
+  SCOPE void kh_resize_##name(kh_##name##_t *h, khint_t new_n_buckets) \
+  {  /* This function uses 0.25*n_buckets bytes of working space instead of */ \
+     /* [sizeof(key_t+val_t)+.25]*n_buckets. */ \
+    khint32_t *new_flags = 0; \
+    khint_t j = 1; \
+    { \
+      kroundup32(new_n_buckets); \
+      if (new_n_buckets < 4) { \
+        new_n_buckets = 4; \
+      } \
+      /* requested size is too small */ \
+      if (h->size >= (khint_t)(new_n_buckets * __ac_HASH_UPPER + 0.5)) { \
+        j = 0; \
+      } else {  /* hash table size to be changed (shrink or expand); rehash */ \
+        new_flags = (khint32_t *)kmalloc(__ac_fsize(new_n_buckets) \
+                                         * sizeof(khint32_t)); \
+        memset(new_flags, 0xaa, \
+               __ac_fsize(new_n_buckets) * sizeof(khint32_t)); \
+        if (h->n_buckets < new_n_buckets) {  /* expand */ \
+          khkey_t *new_keys = (khkey_t *)krealloc((void *)h->keys, new_n_buckets * sizeof(khkey_t)); \
+          h->keys = new_keys; \
+          if (kh_is_map) { \
+            khval_t *new_vals = \
+              (khval_t *)krealloc((void *)h->vals, new_n_buckets * sizeof(khval_t)); \
+            h->vals = new_vals; \
+          } \
+        }  /* otherwise shrink */ \
+      } \
+    } \
+    if (j) {  /* rehashing is needed */ \
+      for (j = 0; j != h->n_buckets; ++j) { \
+        if (__ac_iseither(h->flags, j) == 0) { \
+          khkey_t key = h->keys[j]; \
+          khval_t val; \
+          khint_t new_mask; \
+          new_mask = new_n_buckets - 1; \
+          if (kh_is_map) { \
+            val = h->vals[j]; \
+          } \
+          __ac_set_isdel_true(h->flags, j); \
+          /* kick-out process; sort of like in Cuckoo hashing */ \
+          while (1) { \
+            khint_t k, i, step = 0; \
+            k = __hash_func(key); \
+            i = k & new_mask; \
+            while (!__ac_isempty(new_flags, i)) { \
+              i = (i + (++step)) & new_mask; \
+            } \
+            __ac_set_isempty_false(new_flags, i); \
+            /* kick out the existing element */ \
+            if (i < h->n_buckets && __ac_iseither(h->flags, i) == 0) { \
+              { \
+                khkey_t tmp = h->keys[i]; \
+                h->keys[i] = key; \
+                key = tmp; \
+              } \
+              if (kh_is_map) { \
+                khval_t tmp = h->vals[i]; \
+                h->vals[i] = val; \
+                val = tmp; \
+              } \
+              /* mark it as deleted in the old hash table */ \
+              __ac_set_isdel_true(h->flags, i); \
+            } else {  /* write the element and jump out of the loop */ \
+              h->keys[i] = key; \
+              if (kh_is_map) { \
+                h->vals[i] = val; \
+              } \
+              break; \
+            } \
+          } \
+        } \
+      } \
+      if (h->n_buckets > new_n_buckets) {  /* shrink the hash table */ \
+        h->keys = (khkey_t *)krealloc((void *)h->keys, \
+                                      new_n_buckets * sizeof(khkey_t)); \
+        if (kh_is_map) { \
+          h->vals = (khval_t *)krealloc((void *)h->vals, \
+                                        new_n_buckets * sizeof(khval_t)); \
+        } \
+      } \
+      kfree(h->flags);  /* free the working space */ \
+      h->flags = new_flags; \
+      h->n_buckets = new_n_buckets; \
+      h->n_occupied = h->size; \
+      h->upper_bound = (khint_t)(h->n_buckets * __ac_HASH_UPPER + 0.5); \
+    } \
+  } \
+  SCOPE khint_t kh_put_##name(kh_##name##_t *h, khkey_t key, int *ret) \
+  REAL_FATTR_UNUSED; \
+  SCOPE khint_t kh_put_##name(kh_##name##_t *h, khkey_t key, int *ret) \
+  { \
+    khint_t x; \
+    if (h->n_occupied >= h->upper_bound) {  /* update the hash table */ \
+      if (h->n_buckets > (h->size << 1)) { \
+        kh_resize_##name(h, h->n_buckets - 1);  /* clear "deleted" elements */ \
+      } else { \
+        kh_resize_##name(h, h->n_buckets + 1);  /* expand the hash table */ \
+      } \
+    }  /* TODO: implement automatically shrinking; */ \
+       /* resize() already support shrinking */ \
+    { \
+      khint_t k, i, site, last, mask = h->n_buckets - 1, step = 0; \
+      x = site = h->n_buckets; \
+      k = __hash_func(key); \
+      i = k & mask; \
+      if (__ac_isempty(h->flags, i)) { \
+        x = i;  /* for speed up */ \
+      } else { \
+        last = i; \
+        while (!__ac_isempty(h->flags, i) \
+               && (__ac_isdel(h->flags, i) \
+                   || !__hash_equal(h->keys[i], key))) { \
+          if (__ac_isdel(h->flags, i)) { \
+            site = i; \
+          } \
+          i = (i + (++step)) & mask; \
+          if (i == last) { \
+            x = site; \
+            break; \
+          } \
+        } \
+        if (x == h->n_buckets) { \
+          if (__ac_isempty(h->flags, i) && site != h->n_buckets) { \
+            x = site; \
+          } else { \
+            x = i; \
+          } \
+        } \
+      } \
+    } \
+    if (__ac_isempty(h->flags, x)) {  /* not present at all */ \
+      h->keys[x] = key; \
+      __ac_set_isboth_false(h->flags, x); \
+      h->size++; \
+      h->n_occupied++; \
+      *ret = 1; \
+    } else if (__ac_isdel(h->flags, x)) {  /* deleted */ \
+      h->keys[x] = key; \
+      __ac_set_isboth_false(h->flags, x); \
+      h->size++; \
+      *ret = 2; \
+    } else { \
+      *ret = 0;  /* Don't touch h->keys[x] if present and not deleted */ \
+    } \
+    return x; \
+  } \
+  SCOPE void kh_del_##name(kh_##name##_t *h, khint_t x) \
+  REAL_FATTR_UNUSED; \
+  SCOPE void kh_del_##name(kh_##name##_t *h, khint_t x) \
+  { \
+    if (x != h->n_buckets && !__ac_iseither(h->flags, x)) { \
+      __ac_set_isdel_true(h->flags, x); \
+      --h->size; \
+    } \
+  }
+
+#define KHASH_DECLARE(name, khkey_t, khval_t) \
+  __KHASH_TYPE(name, khkey_t, khval_t) \
+  __KHASH_PROTOTYPES(name, khkey_t, khval_t)
+
+#define KHASH_INIT2(name, SCOPE, khkey_t, khval_t, kh_is_map, __hash_func, __hash_equal) \
+  __KHASH_TYPE(name, khkey_t, khval_t) \
+  __KHASH_IMPL(name, SCOPE, khkey_t, khval_t, kh_is_map, __hash_func, __hash_equal)
+
+#define KHASH_INIT(name, khkey_t, khval_t, kh_is_map, __hash_func, __hash_equal) \
+  KHASH_INIT2(name, static kh_inline, khkey_t, khval_t, kh_is_map, __hash_func, __hash_equal)
+
+// --- BEGIN OF HASH FUNCTIONS ---
+
+/*! @function
+   @abstract     Integer hash function
+   @param  key   The integer [khint32_t]
+   @return       The hash value [khint_t]
+ */
+#define kh_int_hash_func(key) (khint32_t)(key)
+/*! @function
+   @abstract     Integer comparison function
+ */
+#define kh_int_hash_equal(a, b) ((a) == (b))
+/*! @function
+   @abstract     64-bit integer hash function
+   @param  key   The integer [khint64_t]
+   @return       The hash value [khint_t]
+ */
+#define kh_int64_hash_func(key) (khint32_t)((key)>>33^(key)^(key)<<11)
+/*! @function
+   @abstract     64-bit integer comparison function
+ */
+#define kh_int64_hash_equal(a, b) ((a) == (b))
+/*! @function
+   @abstract     const char* hash function
+   @param  s     Pointer to a null terminated string
+   @return       The hash value
+ */
+static kh_inline khint_t __ac_X31_hash_string(const char *s)
+{
+  khint_t h = (khint_t)*s;
+  if (h) {
+    for (++s; *s; ++s) { h = (h << 5) - h + (uint8_t)*s; }
+  }
+  return h;
+}
+/*! @function
+   @abstract     Another interface to const char* hash function
+   @param  key   Pointer to a null terminated string [const char*]
+   @return       The hash value [khint_t]
+ */
+#define kh_str_hash_func(key) __ac_X31_hash_string(key)
+/*! @function
+   @abstract     Const char* comparison function
+ */
+#define kh_str_hash_equal(a, b) (strcmp(a, b) == 0)
+
+static kh_inline khint_t __ac_Wang_hash(khint_t key)
+{
+  key += ~(key << 15);
+  key ^=  (key >> 10);
+  key +=  (key << 3);
+  key ^=  (key >> 6);
+  key += ~(key << 11);
+  key ^=  (key >> 16);
+  return key;
+}
+#define kh_int_hash_func2(k) __ac_Wang_hash((khint_t)key)
+
+// --- END OF HASH FUNCTIONS ---
+
+// Other convenient macros...
+
+/*!
+   @abstract Type of the hash table.
+   @param  name  Name of the hash table [symbol]
+ */
+#define khash_t(name) kh_##name##_t
+
+/*! @function
+   @abstract     Initiate a hash table.
+   @param  name  Name of the hash table [symbol]
+   @return       Pointer to the hash table [khash_t(name)*]
+ */
+#define kh_init(name) kh_init_##name()
+
+/*! @function
+   @abstract     Destroy a hash table.
+   @param  name  Name of the hash table [symbol]
+   @param  h     Pointer to the hash table [khash_t(name)*]
+ */
+#define kh_destroy(name, h) kh_destroy_##name(h)
+
+/*! @function
+   @abstract     Free memory referenced directly inside a hash table.
+   @param  name  Name of the hash table [symbol]
+   @param  h     Pointer to the hash table [khash_t(name)*]
+ */
+#define kh_dealloc(name, h) kh_dealloc_##name(h)
+
+/*! @function
+   @abstract     Reset a hash table without deallocating memory.
+   @param  name  Name of the hash table [symbol]
+   @param  h     Pointer to the hash table [khash_t(name)*]
+ */
+#define kh_clear(name, h) kh_clear_##name(h)
+
+/*! @function
+   @abstract     Resize a hash table.
+   @param  name  Name of the hash table [symbol]
+   @param  h     Pointer to the hash table [khash_t(name)*]
+   @param  s     New size [khint_t]
+ */
+#define kh_resize(name, h, s) kh_resize_##name(h, s)
+
+/*! @function
+   @abstract     Insert a key to the hash table.
+   @param  name  Name of the hash table [symbol]
+   @param  h     Pointer to the hash table [khash_t(name)*]
+   @param  k     Key [type of keys]
+   @param  r     Extra return code: -1 if the operation failed;
+                0 if the key is present in the hash table;
+                1 if the bucket is empty (never used); 2 if the element in
+                the bucket has been deleted [int*]
+   @return       Iterator to the inserted element [khint_t]
+ */
+#define kh_put(name, h, k, r) kh_put_##name(h, k, r)
+
+/*! @function
+   @abstract     Retrieve a key from the hash table.
+   @param  name  Name of the hash table [symbol]
+   @param  h     Pointer to the hash table [khash_t(name)*]
+   @param  k     Key [type of keys]
+   @return       Iterator to the found element, or kh_end(h) if the element is absent [khint_t]
+ */
+#define kh_get(name, h, k) kh_get_##name(h, k)
+
+/*! @function
+   @abstract     Remove a key from the hash table.
+   @param  name  Name of the hash table [symbol]
+   @param  h     Pointer to the hash table [khash_t(name)*]
+   @param  k     Iterator to the element to be deleted [khint_t]
+ */
+#define kh_del(name, h, k) kh_del_##name(h, k)
+
+/*! @function
+   @abstract     Test whether a bucket contains data.
+   @param  h     Pointer to the hash table [khash_t(name)*]
+   @param  x     Iterator to the bucket [khint_t]
+   @return       1 if containing data; 0 otherwise [int]
+ */
+#define kh_exist(h, x) (!__ac_iseither((h)->flags, (x)))
+
+/*! @function
+   @abstract     Get key given an iterator
+   @param  h     Pointer to the hash table [khash_t(name)*]
+   @param  x     Iterator to the bucket [khint_t]
+   @return       Key [type of keys]
+ */
+#define kh_key(h, x) ((h)->keys[x])
+
+/*! @function
+   @abstract     Get value given an iterator
+   @param  h     Pointer to the hash table [khash_t(name)*]
+   @param  x     Iterator to the bucket [khint_t]
+   @return       Value [type of values]
+   @discussion   For hash sets, calling this results in segfault.
+ */
+#define kh_val(h, x) ((h)->vals[x])
+
+/*! @function
+   @abstract     Alias of kh_val()
+ */
+#define kh_value(h, x) ((h)->vals[x])
+
+/*! @function
+   @abstract     Get the start iterator
+   @param  h     Pointer to the hash table [khash_t(name)*]
+   @return       The start iterator [khint_t]
+ */
+#define kh_begin(h) (khint_t)(0)
+
+/*! @function
+   @abstract     Get the end iterator
+   @param  h     Pointer to the hash table [khash_t(name)*]
+   @return       The end iterator [khint_t]
+ */
+#define kh_end(h) ((h)->n_buckets)
+
+/*! @function
+   @abstract     Get the number of elements in the hash table
+   @param  h     Pointer to the hash table [khash_t(name)*]
+   @return       Number of elements in the hash table [khint_t]
+ */
+#define kh_size(h) ((h)->size)
+
+/*! @function
+   @abstract     Get the number of buckets in the hash table
+   @param  h     Pointer to the hash table [khash_t(name)*]
+   @return       Number of buckets in the hash table [khint_t]
+ */
+#define kh_n_buckets(h) ((h)->n_buckets)
+
+/*! @function
+   @abstract     Iterate over the entries in the hash table
+   @param  h     Pointer to the hash table [khash_t(name)*]
+   @param  kvar  Variable to which key will be assigned
+   @param  vvar  Variable to which value will be assigned
+   @param  code  Block of code to execute
+ */
+#define kh_foreach(h, kvar, vvar, code) { khint_t __i; \
+                                          for (__i = kh_begin(h); __i != kh_end(h); ++__i) { \
+                                            if (!kh_exist(h, __i)) continue; \
+                                            (kvar) = kh_key(h, __i); \
+                                            (vvar) = kh_val(h, __i); \
+                                            code; \
+                                          } }
+
+/*! @function
+   @abstract     Iterate over the values in the hash table
+   @param  h     Pointer to the hash table [khash_t(name)*]
+   @param  vvar  Variable to which value will be assigned
+   @param  code  Block of code to execute
+ */
+#define kh_foreach_value(h, vvar, code) { khint_t __i; \
+                                          for (__i = kh_begin(h); __i != kh_end(h); ++__i) { \
+                                            if (!kh_exist(h, __i)) continue; \
+                                            (vvar) = kh_val(h, __i); \
+                                            code; \
+                                          } }
+
+/*! @function
+   @abstract     Iterate over the keys in the hash table
+   @param  h     Pointer to the hash table [khash_t(name)*]
+   @param  kvar  Variable to which value will be assigned
+   @param  code  Block of code to execute
+ */
+#define kh_foreach_key(h, kvar, code) \
+  { \
+    khint_t __i; \
+    for (__i = kh_begin(h); __i != kh_end(h); __i++) { \
+      if (!kh_exist(h, __i)) { \
+        continue; \
+      } \
+      (kvar) = kh_key(h, __i); \
+      code; \
+    } \
+  }
+
+// More convenient interfaces
+
+/*! @function
+   @abstract     Instantiate a hash set containing integer keys
+   @param  name  Name of the hash table [symbol]
+ */
+#define KHASH_SET_INIT_INT(name) \
+  KHASH_INIT(name, khint32_t, char, 0, kh_int_hash_func, kh_int_hash_equal)
+
+/*! @function
+   @abstract     Instantiate a hash map containing integer keys
+   @param  name  Name of the hash table [symbol]
+   @param  khval_t  Type of values [type]
+ */
+#define KHASH_MAP_INIT_INT(name, khval_t) \
+  KHASH_INIT(name, khint32_t, khval_t, 1, kh_int_hash_func, kh_int_hash_equal)
+
+/*! @function
+   @abstract     Instantiate a hash map containing 64-bit integer keys
+   @param  name  Name of the hash table [symbol]
+ */
+#define KHASH_SET_INIT_INT64(name) \
+  KHASH_INIT(name, khint64_t, char, 0, kh_int64_hash_func, kh_int64_hash_equal)
+
+/*! @function
+   @abstract     Instantiate a hash map containing 64-bit integer keys
+   @param  name  Name of the hash table [symbol]
+   @param  khval_t  Type of values [type]
+ */
+#define KHASH_MAP_INIT_INT64(name, khval_t) \
+  KHASH_INIT(name, khint64_t, khval_t, 1, kh_int64_hash_func, kh_int64_hash_equal)
+
+typedef const char *kh_cstr_t;
+/*! @function
+   @abstract     Instantiate a hash map containing const char* keys
+   @param  name  Name of the hash table [symbol]
+ */
+#define KHASH_SET_INIT_STR(name) \
+  KHASH_INIT(name, kh_cstr_t, char, 0, kh_str_hash_func, kh_str_hash_equal)
+
+/*! @function
+   @abstract     Instantiate a hash map containing const char* keys
+   @param  name  Name of the hash table [symbol]
+   @param  khval_t  Type of values [type]
+ */
+#define KHASH_MAP_INIT_STR(name, khval_t) \
+  KHASH_INIT(name, kh_cstr_t, khval_t, 1, kh_str_hash_func, kh_str_hash_equal)
+
+/*! @function
+   @abstract     Return a literal for an empty hash table.
+   @param  name  Name of the hash table [symbol]
+ */
+#define KHASH_EMPTY_TABLE(name) \
+  ((kh_##name##_t) { \
+    .n_buckets = 0, \
+    .size = 0, \
+    .n_occupied = 0, \
+    .upper_bound = 0, \
+    .flags = NULL, \
+    .keys = NULL, \
+    .vals = NULL, \
+  })
+#endif  // NVIM_LIB_KHASH_H