Initial commit.

Translating my Zig library to C for practice.

COPYING

···
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+THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY
+GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE
+USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF
+DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD
+PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS),
+EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
+SUCH DAMAGES.
+
+  17. Interpretation of Sections 15 and 16.
+
+  If the disclaimer of warranty and limitation of liability provided
+above cannot be given local legal effect according to their terms,
+reviewing courts shall apply local law that most closely approximates
+an absolute waiver of all civil liability in connection with the
+Program, unless a warranty or assumption of liability accompanies a
+copy of the Program in return for a fee.
+
+                     END OF TERMS AND CONDITIONS
+
+            How to Apply These Terms to Your New Programs
+
+  If you develop a new program, and you want it to be of the greatest
+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these terms.
+
+  To do so, attach the following notices to the program.  It is safest
+to attach them to the start of each source file to most effectively
+state the exclusion of warranty; and each file should have at least
+the "copyright" line and a pointer to where the full notice is found.
+
+    <one line to give the program's name and a brief idea of what it does.>
+    Copyright (C) <year>  <name of author>
+
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+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
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+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+Also add information on how to contact you by electronic and paper mail.
+
+  If the program does terminal interaction, make it output a short
+notice like this when it starts in an interactive mode:
+
+    <program>  Copyright (C) <year>  <name of author>
+    This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
+    This is free software, and you are welcome to redistribute it
+    under certain conditions; type `show c' for details.
+
+The hypothetical commands `show w' and `show c' should show the appropriate
+parts of the General Public License.  Of course, your program's commands
+might be different; for a GUI interface, you would use an "about box".
+
+  You should also get your employer (if you work as a programmer) or school,
+if any, to sign a "copyright disclaimer" for the program, if necessary.
+For more information on this, and how to apply and follow the GNU GPL, see
+<https://www.gnu.org/licenses/>.
+
+  The GNU General Public License does not permit incorporating your program
+into proprietary programs.  If your program is a subroutine library, you
+may consider it more useful to permit linking proprietary applications with
+the library.  If this is what you want to do, use the GNU Lesser General
+Public License instead of this License.  But first, please read
+<https://www.gnu.org/licenses/why-not-lgpl.html>.

COPYING.LESSER

···
+GNU LESSER GENERAL PUBLIC LICENSE
+                       Version 3, 29 June 2007
+
+ Copyright (C) 2007 Free Software Foundation, Inc. <https://fsf.org/>
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+
+  This version of the GNU Lesser General Public License incorporates
+the terms and conditions of version 3 of the GNU General Public
+License, supplemented by the additional permissions listed below.
+
+  0. Additional Definitions.
+
+  As used herein, "this License" refers to version 3 of the GNU Lesser
+General Public License, and the "GNU GPL" refers to version 3 of the GNU
+General Public License.
+
+  "The Library" refers to a covered work governed by this License,
+other than an Application or a Combined Work as defined below.
+
+  An "Application" is any work that makes use of an interface provided
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+
+  A "Combined Work" is a work produced by combining or linking an
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+
+  The "Minimal Corresponding Source" for a Combined Work means the
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+
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+
+  1. Exception to Section 3 of the GNU GPL.
+
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+
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+
+  6. Revised Versions of the GNU Lesser General Public License.
+
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+differ in detail to address new problems or concerns.
+
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+
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+permanent authorization for you to choose that version for the
+Library.

Makefile

···
+main: include/textstore.h src/textstore.c example/main.c
+	cc -Iinclude/ -Wall -pedantic example/main.c src/textstore.c -o main
+
+cleanup:
+	rm main

README.md

···
+# textstore
+
+A data structure for storing reference-counted, de-duplicated strings for access by other structures.

example/main.c

···
+/**
+ * Runs a tests to make sure the text-store works.
+ */
+
+#include <stdio.h>
+#include <string.h>
+#include <textstore.h>
+
+int main(int argc, char **argv) {
+    textstore_t store;
+    if(textstore_init(&store, 64)) {
+        fprintf(stderr, "ERROR: textstore_init() failed.\n");
+        return 1;
+    }
+
+    // A reference counted string handle.
+    char *handle1_expected = "Hello world!";
+    textstore_handle handle1 = textstore_intern(&store, handle1_expected);
+    if (strcmp(textstore_string(&store, handle1), handle1_expected) != 0) {
+        fprintf(stderr, "ERROR: handle1 does not equal \"%s\"\n", handle1_expected);
+        return 1;
+    }
+
+    char *handle2_expected = "A different string!";
+    textstore_handle handle2 = textstore_intern(&store, handle2_expected);
+    if (strcmp(textstore_string(&store, handle2), handle2_expected)) {
+        fprintf(stderr, "ERROR: handle2 does not equal \"%s\"\n", handle2_expected);
+        return 1;
+    }
+
+    // A handle may become invalidated after all references to it are released.
+    textstore_release(&store, handle1);
+    if (textstore_gc(&store) != 0) {
+        fprintf(stderr, "ERROR: Garbage collector failed.\n");
+        return 1;
+    }
+
+    // Trying to get the data of an inactive handle should return null.
+    char *invalid_string = textstore_string(&store, handle1);
+    if (invalid_string != NULL) {
+        fprintf(stderr, "ERROR: handle1 should be null, but isn't: \"%s\"\n", invalid_string);
+        return 1;
+    }
+
+    // Interning new strings may re-use previously gc'd handle indexes.
+    // But they are not equal due to their cycle bits.
+    textstore_handle handle3 = textstore_intern(&store, "Hello world.");
+    if (handle1 == handle3) {
+        fprintf(stderr, "ERROR: handle1 and handle3 should not be equal.\n");
+        return 1;
+    }
+
+    // And trying to access a previously gc'd handle will still return an error,
+    // even if its index is in use.
+    invalid_string = textstore_string(&store, handle1);
+    if (invalid_string != NULL) {
+        fprintf(stderr, "ERROR: handle1 should be null, but isn't: \"%s\"\n", invalid_string);
+        return 1;
+    }
+
+    // Likewise, interning the same string will result in identical handles.
+    textstore_handle handle4 = textstore_intern(&store, "Hello world.");
+    if (handle3 != handle4) {
+        fprintf(stderr, "ERROR: handle3 and handle4 should be equal.\n");
+        return 1;
+    }
+
+    {
+        textstore_handle temp_handle;
+        temp_handle = textstore_intern(&store, "blah blah");
+        textstore_release(&store, temp_handle);
+        temp_handle = textstore_intern(&store, "random text");
+        textstore_release(&store, temp_handle);
+        temp_handle = textstore_intern(&store, "text");
+        textstore_release(&store, temp_handle);
+        temp_handle = textstore_intern(&store, "random text2");
+        textstore_release(&store, temp_handle);
+    }
+
+    textstore_handle handle5 = textstore_intern(&store, "All your bases...");
+    textstore_gc(&store);
+    // Even after a GC and the underlying text being invalidated and shifted
+    // about, valid handles can still be used.
+    if (strcmp(textstore_string(&store, handle5), "All your bases...") != 0) {
+        fprintf(stderr, "ERROR: handle5 is wrong? \"%s\"\n", textstore_string(&store, handle5));
+        return 1;
+    }
+
+    textstore_free(&store);
+
+    printf("All tests passed.\n");
+    return 0;
+}
+

include/textstore.h

···
+/* text-store - A store for storing reference-counted, de-duplicated strings.
+ * Copyright (C) 2025 Jeremia Dominguez <[e-mail]>
+ * 
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+
+#ifndef TEXTSTORE_H
+#define TEXTSTORE_H
+
+#include <assert.h>
+#include <stdbool.h>
+#include <stddef.h>
+#include <stdint.h>
+
+/**
+ * A handle used to reference a string within the text store.
+ */
+typedef uint64_t textstore_handle;
+#define TEXTSTORE_HANDLE_ERROR UINT64_MAX
+
+typedef struct {
+    uint32_t offset;
+    uint32_t len;
+} textstore_slice;
+
+/**
+ * A store containing all string data.
+ */
+typedef struct textstore_t {
+    char             *buffer;     /* Buffer of all allocated text.
+                                      Pointers to this buffer are considered volatile. */
+    uint32_t         length;      /* Length of currently used buffer. */
+    uint32_t         buffer_cap;  /* The current capacity of the buffer. */
+    uint32_t         available;   /* Count of available free handles. */
+
+    uint32_t         *map;        /* The hashmap's indexes into the tables below. */
+    textstore_slice  *key;        /* The slice a handle represents within the buffer */
+    uint32_t         *ref;        /* The reference counter for a given string. */
+    uint32_t         *generation; /* The current/last active generation of a handle. */
+    bool             *active;     /* Whether the given handle is currently active. */
+
+    uint32_t         count;       /* The number of string entries. */
+    uint32_t         capacity;    /* The current capacity of the hashmap. */
+} textstore_t;
+
+int textstore_init(textstore_t *store, uint32_t initial_buffer);
+void textstore_free(textstore_t *store);
+int textstore_gc(textstore_t *store);
+textstore_handle textstore_intern(textstore_t *store, char *str);
+textstore_handle textstore_intern_len(textstore_t *store, char *str, uint32_t len);
+
+static inline uint32_t textstore_as_index(textstore_handle handle) {
+    return (uint32_t) (handle & 0xFFFFFFFF);
+}
+static inline uint32_t textstore_as_generation(textstore_handle handle) {
+    return (uint32_t) (handle >> 32);
+}
+
+static inline char *textstore_string(textstore_t *store, textstore_handle handle) {
+    textstore_t sstore = *store;
+    uint32_t index = textstore_as_index(handle);
+    if (index > sstore.count || !sstore.active[index]) return NULL;
+
+    uint32_t generation = textstore_as_generation(handle);
+    if (generation != sstore.generation[index]) return NULL;
+
+    return sstore.buffer + sstore.key[index].offset;
+}
+
+static inline uint32_t textstore_length(textstore_t *store, textstore_handle handle) {
+    textstore_t sstore = *store;
+    uint32_t index = textstore_as_index(handle);
+    if (index == 0 || index > sstore.count || !sstore.active[index]) return 0;
+
+    uint32_t generation = textstore_as_generation(handle);
+    if (generation != sstore.generation[index]) return 0;
+
+    return sstore.key[index].len;
+}
+
+static inline void textstore_retain(textstore_t *store, textstore_handle handle) {
+    uint32_t index = textstore_as_index(handle);
+    assert(index < store->count);
+    assert(store->active[index]);
+
+    store->ref[index] += 1;
+}
+
+static inline void textstore_release(textstore_t *store, textstore_handle handle) {
+    uint32_t index = textstore_as_index(handle);
+    assert(index < store->count);
+    assert(store->active[index]);
+
+    // Avoid underflow.
+    uint32_t ref = store->ref[index];
+    if (ref) {
+        store->ref[index] = ref - 1;
+    }
+}
+
+#endif // TEXTSTORE_H

src/rapidhash.h

···
+/*
+ * rapidhash V3 - Very fast, high quality, platform-independent hashing algorithm.
+ *
+ * Based on 'wyhash', by Wang Yi <[e-mail]>
+ * 
+ * Copyright (C) 2025 Nicolas De Carli
+ *
+ * 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.
+ *
+ * You can contact the author at:
+ *   - rapidhash source repository: https://github.com/Nicoshev/rapidhash
+ */
+
+ #pragma once
+ 
+/*
+ *  Includes.
+ */
+ #include <stdint.h>
+ #include <string.h>
+ #if defined(_MSC_VER)
+ # include <intrin.h>
+ # if defined(_M_X64) && !defined(_M_ARM64EC)
+ #   pragma intrinsic(_umul128)
+ # endif
+ #endif
+ 
+ /*
+  *  C/C++ macros.
+  */
+ 
+ #ifdef _MSC_VER
+ # define RAPIDHASH_ALWAYS_INLINE __forceinline
+ #elif defined(__GNUC__)
+ # define RAPIDHASH_ALWAYS_INLINE inline __attribute__((__always_inline__))
+ #else
+ # define RAPIDHASH_ALWAYS_INLINE inline
+ #endif
+ 
+ #ifdef __cplusplus
+ # define RAPIDHASH_NOEXCEPT noexcept
+ # define RAPIDHASH_CONSTEXPR constexpr
+ # ifndef RAPIDHASH_INLINE
+ #   define RAPIDHASH_INLINE RAPIDHASH_ALWAYS_INLINE
+ # endif
+ # if __cplusplus >= 201402L && !defined(_MSC_VER)
+ #   define RAPIDHASH_INLINE_CONSTEXPR RAPIDHASH_ALWAYS_INLINE constexpr
+ # else
+ #   define RAPIDHASH_INLINE_CONSTEXPR RAPIDHASH_ALWAYS_INLINE
+ # endif
+ #else
+ # define RAPIDHASH_NOEXCEPT
+ # define RAPIDHASH_CONSTEXPR static const
+ # ifndef RAPIDHASH_INLINE
+ #   define RAPIDHASH_INLINE static RAPIDHASH_ALWAYS_INLINE
+ # endif
+ # define RAPIDHASH_INLINE_CONSTEXPR RAPIDHASH_INLINE
+ #endif
+
+ /*
+  *  Unrolled macro.
+  *  Improves large input speed, but increases code size and worsens small input speed.
+  *
+  *  RAPIDHASH_COMPACT: Normal behavior.
+  *  RAPIDHASH_UNROLLED: 
+  *
+  */
+  #ifndef RAPIDHASH_UNROLLED
+  # define RAPIDHASH_COMPACT
+  #elif defined(RAPIDHASH_COMPACT)
+  # error "cannot define RAPIDHASH_COMPACT and RAPIDHASH_UNROLLED simultaneously."
+  #endif
+ 
+ /*
+  *  Protection macro, alters behaviour of rapid_mum multiplication function.
+  *
+  *  RAPIDHASH_FAST: Normal behavior, max speed.
+  *  RAPIDHASH_PROTECTED: Extra protection against entropy loss.
+  */
+ #ifndef RAPIDHASH_PROTECTED
+ # define RAPIDHASH_FAST
+ #elif defined(RAPIDHASH_FAST)
+ # error "cannot define RAPIDHASH_PROTECTED and RAPIDHASH_FAST simultaneously."
+ #endif
+ 
+ /*
+  *  Likely and unlikely macros.
+  */
+ #if defined(__GNUC__) || defined(__INTEL_COMPILER) || defined(__clang__)
+ # define _likely_(x)  __builtin_expect(x,1)
+ # define _unlikely_(x)  __builtin_expect(x,0)
+ #else
+ # define _likely_(x) (x)
+ # define _unlikely_(x) (x)
+ #endif
+ 
+ /*
+  *  Endianness macros.
+  */
+ #ifndef RAPIDHASH_LITTLE_ENDIAN
+ # if defined(_WIN32) || defined(__LITTLE_ENDIAN__) || (defined(__BYTE_ORDER__) && __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__)
+ #   define RAPIDHASH_LITTLE_ENDIAN
+ # elif defined(__BIG_ENDIAN__) || (defined(__BYTE_ORDER__) && __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__)
+ #   define RAPIDHASH_BIG_ENDIAN
+ # else
+ #   warning "could not determine endianness! Falling back to little endian."
+ #   define RAPIDHASH_LITTLE_ENDIAN
+ # endif
+ #endif
+ 
+ /*
+  *  Default secret parameters.
+  */
+   RAPIDHASH_CONSTEXPR uint64_t rapid_secret[8] = {
+     0x2d358dccaa6c78a5ull,
+     0x8bb84b93962eacc9ull,
+     0x4b33a62ed433d4a3ull,
+     0x4d5a2da51de1aa47ull,
+     0xa0761d6478bd642full,
+     0xe7037ed1a0b428dbull,
+     0x90ed1765281c388cull,
+     0xaaaaaaaaaaaaaaaaull};
+ 
+ /*
+  *  64*64 -> 128bit multiply function.
+  *
+  *  @param A  Address of 64-bit number.
+  *  @param B  Address of 64-bit number.
+  *
+  *  Calculates 128-bit C = *A * *B.
+  *
+  *  When RAPIDHASH_FAST is defined:
+  *  Overwrites A contents with C's low 64 bits.
+  *  Overwrites B contents with C's high 64 bits.
+  *
+  *  When RAPIDHASH_PROTECTED is defined:
+  *  Xors and overwrites A contents with C's low 64 bits.
+  *  Xors and overwrites B contents with C's high 64 bits.
+  */
+ RAPIDHASH_INLINE_CONSTEXPR void rapid_mum(uint64_t *A, uint64_t *B) RAPIDHASH_NOEXCEPT {
+ #if defined(__SIZEOF_INT128__)
+   __uint128_t r=*A; r*=*B;
+   #ifdef RAPIDHASH_PROTECTED
+   *A^=(uint64_t)r; *B^=(uint64_t)(r>>64);
+   #else
+   *A=(uint64_t)r; *B=(uint64_t)(r>>64);
+   #endif
+ #elif defined(_MSC_VER) && (defined(_WIN64) || defined(_M_HYBRID_CHPE_ARM64))
+   #if defined(_M_X64)
+     #ifdef RAPIDHASH_PROTECTED
+     uint64_t a, b;
+     a=_umul128(*A,*B,&b);
+     *A^=a;  *B^=b;
+     #else
+     *A=_umul128(*A,*B,B);
+     #endif
+   #else
+     #ifdef RAPIDHASH_PROTECTED
+     uint64_t a, b;
+     b = __umulh(*A, *B);
+     a = *A * *B;
+     *A^=a;  *B^=b;
+     #else
+     uint64_t c = __umulh(*A, *B);
+     *A = *A * *B;
+     *B = c;
+     #endif
+   #endif
+ #else
+   uint64_t ha=*A>>32, hb=*B>>32, la=(uint32_t)*A, lb=(uint32_t)*B;
+   uint64_t rh=ha*hb, rm0=ha*lb, rm1=hb*la, rl=la*lb, t=rl+(rm0<<32), c=t<rl;
+   uint64_t lo=t+(rm1<<32); 
+   c+=lo<t; 
+   uint64_t hi=rh+(rm0>>32)+(rm1>>32)+c;
+   #ifdef RAPIDHASH_PROTECTED
+   *A^=lo;  *B^=hi;
+   #else
+   *A=lo;  *B=hi;
+   #endif
+ #endif
+ }
+ 
+ /*
+  *  Multiply and xor mix function.
+  *
+  *  @param A  64-bit number.
+  *  @param B  64-bit number.
+  *
+  *  Calculates 128-bit C = A * B.
+  *  Returns 64-bit xor between high and low 64 bits of C.
+  */
+  RAPIDHASH_INLINE_CONSTEXPR uint64_t rapid_mix(uint64_t A, uint64_t B) RAPIDHASH_NOEXCEPT { rapid_mum(&A,&B); return A^B; }
+ 
+ /*
+  *  Read functions.
+  */
+ #ifdef RAPIDHASH_LITTLE_ENDIAN
+ RAPIDHASH_INLINE uint64_t rapid_read64(const uint8_t *p) RAPIDHASH_NOEXCEPT { uint64_t v; memcpy(&v, p, sizeof(uint64_t)); return v;}
+ RAPIDHASH_INLINE uint64_t rapid_read32(const uint8_t *p) RAPIDHASH_NOEXCEPT { uint32_t v; memcpy(&v, p, sizeof(uint32_t)); return v;}
+ #elif defined(__GNUC__) || defined(__INTEL_COMPILER) || defined(__clang__)
+ RAPIDHASH_INLINE uint64_t rapid_read64(const uint8_t *p) RAPIDHASH_NOEXCEPT { uint64_t v; memcpy(&v, p, sizeof(uint64_t)); return __builtin_bswap64(v);}
+ RAPIDHASH_INLINE uint64_t rapid_read32(const uint8_t *p) RAPIDHASH_NOEXCEPT { uint32_t v; memcpy(&v, p, sizeof(uint32_t)); return __builtin_bswap32(v);}
+ #elif defined(_MSC_VER)
+ RAPIDHASH_INLINE uint64_t rapid_read64(const uint8_t *p) RAPIDHASH_NOEXCEPT { uint64_t v; memcpy(&v, p, sizeof(uint64_t)); return _byteswap_uint64(v);}
+ RAPIDHASH_INLINE uint64_t rapid_read32(const uint8_t *p) RAPIDHASH_NOEXCEPT { uint32_t v; memcpy(&v, p, sizeof(uint32_t)); return _byteswap_ulong(v);}
+ #else
+ RAPIDHASH_INLINE uint64_t rapid_read64(const uint8_t *p) RAPIDHASH_NOEXCEPT {
+   uint64_t v; memcpy(&v, p, 8);
+   return (((v >> 56) & 0xff)| ((v >> 40) & 0xff00)| ((v >> 24) & 0xff0000)| ((v >>  8) & 0xff000000)| ((v <<  8) & 0xff00000000)| ((v << 24) & 0xff0000000000)| ((v << 40) & 0xff000000000000)| ((v << 56) & 0xff00000000000000));
+ }
+ RAPIDHASH_INLINE uint64_t rapid_read32(const uint8_t *p) RAPIDHASH_NOEXCEPT {
+   uint32_t v; memcpy(&v, p, 4);
+   return (((v >> 24) & 0xff)| ((v >>  8) & 0xff00)| ((v <<  8) & 0xff0000)| ((v << 24) & 0xff000000));
+ }
+ #endif
+ 
+ /*
+  *  rapidhash main function.
+  *
+  *  @param key     Buffer to be hashed.
+  *  @param len     @key length, in bytes.
+  *  @param seed    64-bit seed used to alter the hash result predictably.
+  *  @param secret  Triplet of 64-bit secrets used to alter hash result predictably.
+  *
+  *  Returns a 64-bit hash.
+  */
+RAPIDHASH_INLINE_CONSTEXPR uint64_t rapidhash_internal(const void *key, size_t len, uint64_t seed, const uint64_t* secret) RAPIDHASH_NOEXCEPT {
+  const uint8_t *p=(const uint8_t *)key;
+  seed ^= rapid_mix(seed ^ secret[2], secret[1]);
+  uint64_t a=0, b=0;
+  size_t i = len;
+  if (_likely_(len <= 16)) {
+    if (len >= 4) {
+      seed ^= len;
+      if (len >= 8) {
+        const uint8_t* plast = p + len - 8;
+        a = rapid_read64(p);
+        b = rapid_read64(plast);
+      } else {
+        const uint8_t* plast = p + len - 4;
+        a = rapid_read32(p);
+        b = rapid_read32(plast);
+      }
+    } else if (len > 0) {
+      a = (((uint64_t)p[0])<<45)|p[len-1];
+      b = p[len>>1];
+    } else
+      a = b = 0;
+  } else {
+    if (len > 112) {
+      uint64_t see1 = seed, see2 = seed;
+      uint64_t see3 = seed, see4 = seed;
+      uint64_t see5 = seed, see6 = seed;
+#ifdef RAPIDHASH_COMPACT
+      do {
+        seed = rapid_mix(rapid_read64(p) ^ secret[0], rapid_read64(p + 8) ^ seed);
+        see1 = rapid_mix(rapid_read64(p + 16) ^ secret[1], rapid_read64(p + 24) ^ see1);
+        see2 = rapid_mix(rapid_read64(p + 32) ^ secret[2], rapid_read64(p + 40) ^ see2);
+        see3 = rapid_mix(rapid_read64(p + 48) ^ secret[3], rapid_read64(p + 56) ^ see3);
+        see4 = rapid_mix(rapid_read64(p + 64) ^ secret[4], rapid_read64(p + 72) ^ see4);
+        see5 = rapid_mix(rapid_read64(p + 80) ^ secret[5], rapid_read64(p + 88) ^ see5);
+        see6 = rapid_mix(rapid_read64(p + 96) ^ secret[6], rapid_read64(p + 104) ^ see6);
+        p += 112;
+        i -= 112;
+      } while(i > 112);
+#else
+      while (i > 224) {
+        seed = rapid_mix(rapid_read64(p) ^ secret[0], rapid_read64(p + 8) ^ seed);
+        see1 = rapid_mix(rapid_read64(p + 16) ^ secret[1], rapid_read64(p + 24) ^ see1);
+        see2 = rapid_mix(rapid_read64(p + 32) ^ secret[2], rapid_read64(p + 40) ^ see2);
+        see3 = rapid_mix(rapid_read64(p + 48) ^ secret[3], rapid_read64(p + 56) ^ see3);
+        see4 = rapid_mix(rapid_read64(p + 64) ^ secret[4], rapid_read64(p + 72) ^ see4);
+        see5 = rapid_mix(rapid_read64(p + 80) ^ secret[5], rapid_read64(p + 88) ^ see5);
+        see6 = rapid_mix(rapid_read64(p + 96) ^ secret[6], rapid_read64(p + 104) ^ see6);
+        seed = rapid_mix(rapid_read64(p + 112) ^ secret[0], rapid_read64(p + 120) ^ seed);
+        see1 = rapid_mix(rapid_read64(p + 128) ^ secret[1], rapid_read64(p + 136) ^ see1);
+        see2 = rapid_mix(rapid_read64(p + 144) ^ secret[2], rapid_read64(p + 152) ^ see2);
+        see3 = rapid_mix(rapid_read64(p + 160) ^ secret[3], rapid_read64(p + 168) ^ see3);
+        see4 = rapid_mix(rapid_read64(p + 176) ^ secret[4], rapid_read64(p + 184) ^ see4);
+        see5 = rapid_mix(rapid_read64(p + 192) ^ secret[5], rapid_read64(p + 200) ^ see5);
+        see6 = rapid_mix(rapid_read64(p + 208) ^ secret[6], rapid_read64(p + 216) ^ see6);
+        p += 224;
+        i -= 224;
+      }
+      if (i > 112) {
+        seed = rapid_mix(rapid_read64(p) ^ secret[0], rapid_read64(p + 8) ^ seed);
+        see1 = rapid_mix(rapid_read64(p + 16) ^ secret[1], rapid_read64(p + 24) ^ see1);
+        see2 = rapid_mix(rapid_read64(p + 32) ^ secret[2], rapid_read64(p + 40) ^ see2);
+        see3 = rapid_mix(rapid_read64(p + 48) ^ secret[3], rapid_read64(p + 56) ^ see3);
+        see4 = rapid_mix(rapid_read64(p + 64) ^ secret[4], rapid_read64(p + 72) ^ see4);
+        see5 = rapid_mix(rapid_read64(p + 80) ^ secret[5], rapid_read64(p + 88) ^ see5);
+        see6 = rapid_mix(rapid_read64(p + 96) ^ secret[6], rapid_read64(p + 104) ^ see6);
+        p += 112;
+        i -= 112;
+      }
+#endif
+      seed ^= see1;
+      see2 ^= see3;
+      see4 ^= see5;
+      seed ^= see6;
+      see2 ^= see4;
+      seed ^= see2;
+    }
+    if (i > 16) {
+      seed = rapid_mix(rapid_read64(p) ^ secret[2], rapid_read64(p + 8) ^ seed);
+      if (i > 32) {
+          seed = rapid_mix(rapid_read64(p + 16) ^ secret[2], rapid_read64(p + 24) ^ seed);
+          if (i > 48) {
+              seed = rapid_mix(rapid_read64(p + 32) ^ secret[1], rapid_read64(p + 40) ^ seed);
+              if (i > 64) {
+                  seed = rapid_mix(rapid_read64(p + 48) ^ secret[1], rapid_read64(p + 56) ^ seed);
+                  if (i > 80) {
+                      seed = rapid_mix(rapid_read64(p + 64) ^ secret[2], rapid_read64(p + 72) ^ seed);
+                      if (i > 96) {
+                          seed = rapid_mix(rapid_read64(p + 80) ^ secret[1], rapid_read64(p + 88) ^ seed);
+                      }
+                  }
+              }
+          }
+      }
+    }
+    a=rapid_read64(p+i-16) ^ i;  b=rapid_read64(p+i-8);
+  }
+  a ^= secret[1];
+  b ^= seed;
+  rapid_mum(&a, &b);
+  return rapid_mix(a ^ secret[7], b ^ secret[1] ^ i);
+}
+
+ /*
+  *  rapidhashMicro main function.
+  *
+  *  @param key     Buffer to be hashed.
+  *  @param len     @key length, in bytes.
+  *  @param seed    64-bit seed used to alter the hash result predictably.
+  *  @param secret  Triplet of 64-bit secrets used to alter hash result predictably.
+  *
+  *  Returns a 64-bit hash.
+  */
+  RAPIDHASH_INLINE_CONSTEXPR uint64_t rapidhashMicro_internal(const void *key, size_t len, uint64_t seed, const uint64_t* secret) RAPIDHASH_NOEXCEPT {
+    const uint8_t *p=(const uint8_t *)key;
+    seed ^= rapid_mix(seed ^ secret[2], secret[1]);
+    uint64_t a=0, b=0;
+    size_t i = len;
+    if (_likely_(len <= 16)) {
+      if (len >= 4) {
+        seed ^= len;
+        if (len >= 8) {
+          const uint8_t* plast = p + len - 8;
+          a = rapid_read64(p);
+          b = rapid_read64(plast);
+        } else {
+          const uint8_t* plast = p + len - 4;
+          a = rapid_read32(p);
+          b = rapid_read32(plast);
+        }
+      } else if (len > 0) {
+        a = (((uint64_t)p[0])<<45)|p[len-1];
+        b = p[len>>1];
+      } else
+        a = b = 0;
+    } else {
+      if (i > 80) {
+        uint64_t see1 = seed, see2 = seed;
+        uint64_t see3 = seed, see4 = seed;
+        do {
+          seed = rapid_mix(rapid_read64(p) ^ secret[0], rapid_read64(p + 8) ^ seed);
+          see1 = rapid_mix(rapid_read64(p + 16) ^ secret[1], rapid_read64(p + 24) ^ see1);
+          see2 = rapid_mix(rapid_read64(p + 32) ^ secret[2], rapid_read64(p + 40) ^ see2);
+          see3 = rapid_mix(rapid_read64(p + 48) ^ secret[3], rapid_read64(p + 56) ^ see3);
+          see4 = rapid_mix(rapid_read64(p + 64) ^ secret[4], rapid_read64(p + 72) ^ see4);
+          p += 80;
+          i -= 80;
+        } while(i > 80);
+        seed ^= see1;
+        see2 ^= see3;
+        seed ^= see4;
+        seed ^= see2;
+      }
+      if (i > 16) {
+        seed = rapid_mix(rapid_read64(p) ^ secret[2], rapid_read64(p + 8) ^ seed);
+        if (i > 32) {
+            seed = rapid_mix(rapid_read64(p + 16) ^ secret[2], rapid_read64(p + 24) ^ seed);
+            if (i > 48) {
+                seed = rapid_mix(rapid_read64(p + 32) ^ secret[1], rapid_read64(p + 40) ^ seed);
+                if (i > 64) {
+                    seed = rapid_mix(rapid_read64(p + 48) ^ secret[1], rapid_read64(p + 56) ^ seed);
+                }
+            }
+        }
+      }
+      a=rapid_read64(p+i-16) ^ i;  b=rapid_read64(p+i-8);
+    }
+    a ^= secret[1];
+    b ^= seed;
+    rapid_mum(&a, &b);
+    return rapid_mix(a ^ secret[7], b ^ secret[1] ^ i);
+  }
+
+  /*
+  *  rapidhashNano main function.
+  *
+  *  @param key     Buffer to be hashed.
+  *  @param len     @key length, in bytes.
+  *  @param seed    64-bit seed used to alter the hash result predictably.
+  *  @param secret  Triplet of 64-bit secrets used to alter hash result predictably.
+  *
+  *  Returns a 64-bit hash.
+  */
+  RAPIDHASH_INLINE_CONSTEXPR uint64_t rapidhashNano_internal(const void *key, size_t len, uint64_t seed, const uint64_t* secret) RAPIDHASH_NOEXCEPT {
+    const uint8_t *p=(const uint8_t *)key;
+    seed ^= rapid_mix(seed ^ secret[2], secret[1]);
+    uint64_t a=0, b=0;
+    size_t i = len;
+    if (_likely_(len <= 16)) {
+      if (len >= 4) {
+        seed ^= len;
+        if (len >= 8) {
+          const uint8_t* plast = p + len - 8;
+          a = rapid_read64(p);
+          b = rapid_read64(plast);
+        } else {
+          const uint8_t* plast = p + len - 4;
+          a = rapid_read32(p);
+          b = rapid_read32(plast);
+        }
+      } else if (len > 0) {
+        a = (((uint64_t)p[0])<<45)|p[len-1];
+        b = p[len>>1];
+      } else
+        a = b = 0;
+    } else {
+      if (i > 48) {
+        uint64_t see1 = seed, see2 = seed;
+        do {
+          seed = rapid_mix(rapid_read64(p) ^ secret[0], rapid_read64(p + 8) ^ seed);
+          see1 = rapid_mix(rapid_read64(p + 16) ^ secret[1], rapid_read64(p + 24) ^ see1);
+          see2 = rapid_mix(rapid_read64(p + 32) ^ secret[2], rapid_read64(p + 40) ^ see2);
+          p += 48;
+          i -= 48;
+        } while(i > 48);
+        seed ^= see1;
+        seed ^= see2;
+      }
+      if (i > 16) {
+        seed = rapid_mix(rapid_read64(p) ^ secret[2], rapid_read64(p + 8) ^ seed);
+        if (i > 32) {
+            seed = rapid_mix(rapid_read64(p + 16) ^ secret[2], rapid_read64(p + 24) ^ seed);
+        }
+      }
+      a=rapid_read64(p+i-16) ^ i;  b=rapid_read64(p+i-8);
+    }
+    a ^= secret[1];
+    b ^= seed;
+    rapid_mum(&a, &b);
+    return rapid_mix(a ^ secret[7], b ^ secret[1] ^ i);
+  }
+ 
+/*
+ *  rapidhash seeded hash function.
+ *
+ *  @param key     Buffer to be hashed.
+ *  @param len     @key length, in bytes.
+ *  @param seed    64-bit seed used to alter the hash result predictably.
+ *
+ *  Calls rapidhash_internal using provided parameters and default secrets.
+ *
+ *  Returns a 64-bit hash.
+ */
+RAPIDHASH_INLINE_CONSTEXPR uint64_t rapidhash_withSeed(const void *key, size_t len, uint64_t seed) RAPIDHASH_NOEXCEPT {
+  return rapidhash_internal(key, len, seed, rapid_secret);
+}
+ 
+/*
+ *  rapidhash general purpose hash function.
+ *
+ *  @param key     Buffer to be hashed.
+ *  @param len     @key length, in bytes.
+ *
+ *  Calls rapidhash_withSeed using provided parameters and the default seed.
+ *
+ *  Returns a 64-bit hash.
+ */
+RAPIDHASH_INLINE_CONSTEXPR uint64_t rapidhash(const void *key, size_t len) RAPIDHASH_NOEXCEPT {
+  return rapidhash_withSeed(key, len, 0);
+}
+
+/*
+ *  rapidhashMicro seeded hash function.
+ *
+ *  Designed for HPC and server applications, where cache misses make a noticeable performance detriment.
+ *  Clang-18+ compiles it to ~140 instructions without stack usage, both on x86-64 and aarch64.
+ *  Faster for sizes up to 512 bytes, just 15%-20% slower for inputs above 1kb.
+ *
+ *  @param key     Buffer to be hashed.
+ *  @param len     @key length, in bytes.
+ *  @param seed    64-bit seed used to alter the hash result predictably.
+ *
+ *  Calls rapidhash_internal using provided parameters and default secrets.
+ *
+ *  Returns a 64-bit hash.
+ */
+ RAPIDHASH_INLINE_CONSTEXPR uint64_t rapidhashMicro_withSeed(const void *key, size_t len, uint64_t seed) RAPIDHASH_NOEXCEPT {
+  return rapidhashMicro_internal(key, len, seed, rapid_secret);
+}
+ 
+/*
+ *  rapidhashMicro hash function.
+ *
+ *  @param key     Buffer to be hashed.
+ *  @param len     @key length, in bytes.
+ *
+ *  Calls rapidhash_withSeed using provided parameters and the default seed.
+ *
+ *  Returns a 64-bit hash.
+ */
+RAPIDHASH_INLINE_CONSTEXPR uint64_t rapidhashMicro(const void *key, size_t len) RAPIDHASH_NOEXCEPT {
+  return rapidhashMicro_withSeed(key, len, 0);
+}
+
+/*
+ *  rapidhashNano seeded hash function.
+ *
+ *  @param key     Buffer to be hashed.
+ *  @param len     @key length, in bytes.
+ *  @param seed    64-bit seed used to alter the hash result predictably.
+ *
+ *  Calls rapidhash_internal using provided parameters and default secrets.
+ *
+ *  Returns a 64-bit hash.
+ */
+ RAPIDHASH_INLINE_CONSTEXPR uint64_t rapidhashNano_withSeed(const void *key, size_t len, uint64_t seed) RAPIDHASH_NOEXCEPT {
+  return rapidhashNano_internal(key, len, seed, rapid_secret);
+}
+ 
+/*
+ *  rapidhashNano hash function.
+ *
+ *  Designed for Mobile and embedded applications, where keeping a small code size is a top priority.
+ *  Clang-18+ compiles it to less than 100 instructions without stack usage, both on x86-64 and aarch64.
+ *  The fastest for sizes up to 48 bytes, but may be considerably slower for larger inputs.
+ *
+ *  @param key     Buffer to be hashed.
+ *  @param len     @key length, in bytes.
+ *
+ *  Calls rapidhash_withSeed using provided parameters and the default seed.
+ *
+ *  Returns a 64-bit hash.
+ */
+RAPIDHASH_INLINE_CONSTEXPR uint64_t rapidhashNano(const void *key, size_t len) RAPIDHASH_NOEXCEPT {
+  return rapidhashNano_withSeed(key, len, 0);
+}

src/textstore.c

···
+/* text-store - A store for storing reference-counted, de-duplicated strings.
+ * Copyright (C) 2025 Jeremia Dominguez <[e-mail]>
+ * 
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+#include <alloca.h>
+#include <stdalign.h>
+#include <stdbool.h>
+#include <stddef.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <textstore.h>
+
+#include "rapidhash.h"
+
+/* Size of struct-of-array member's items. */
+#define SoASize (sizeof(uint32_t) + sizeof(textstore_slice) + (sizeof(uint32_t) * 2) + sizeof(bool))
+
+static inline textstore_handle to_handle(uint32_t index, uint32_t generation) {
+    uint64_t handle = (uint64_t)generation << 32;
+    handle += index;
+    return handle;
+}
+
+/**
+ * Allocates enough room on the hash map for n items, and sets the store's pointers.
+ *
+ * Note: Use on a temporary copy.
+ */
+static inline void textstore_alloc(textstore_t *store, size_t n) {
+    store->map = (uint32_t *)aligned_alloc(alignof(uint32_t), SoASize * n);
+    store->key = (textstore_slice *)(store->map + n);
+    store->ref = (uint32_t *)(store->key + n);
+    store->generation = (uint32_t *)(store->ref + n);
+    store->active = (bool *)(store->generation + n);
+}
+
+static void textstore_put(textstore_t *store,  char *str, uint32_t len, uint32_t value) {
+    uint32_t *map     = store->map;
+    uint32_t capacity = store->capacity;
+    uint32_t idx      = rapidhash(str, len) % capacity;
+    while (map[idx] != 0) { /* The 0 index is already reserved for empty string. */
+        idx = (idx + 1) % capacity;
+    }
+    map[idx] = value;
+}
+
+static void textstore_rehash(textstore_t *store) {
+    char             *buffer  = store->buffer;
+    textstore_slice *slices  = store->key + 1; /* Skip index 0, empty string. */
+    bool             *active  = store->active + 1;
+    uint32_t         count    = store->count - 1;
+    memset(store->map, 0, sizeof(uint32_t) * store->capacity);
+    for (uint32_t i = 0; i < count; i++) {
+        if (active[i]) {
+            textstore_slice slice = slices[i];
+            textstore_put(store, &buffer[slice.offset], slice.len, i + 1);
+        }
+    }
+}
+
+static textstore_handle textstore_find(textstore_t *store, char *str, uint32_t len) {
+    assert(str != NULL);
+    assert(len != 0);
+
+    char             *buffer  = store->buffer;
+    uint32_t         capacity = store->capacity;
+    uint32_t         *map     = store->map;
+    textstore_slice *key     = store->key;
+    bool             *active  = store->active;
+
+    uint32_t index = rapidhash(str, len) % capacity;
+    while (map[index] != 0) {
+        uint32_t idx = map[index];
+        if (key[idx].len != len || !active[idx]) {
+            index = (index + 1) % capacity;
+            continue;
+        }
+        if (strcmp(str, &buffer[key[idx].offset]) == 0) {
+            return to_handle(idx, store->generation[idx]);
+        }
+    }
+
+    return TEXTSTORE_HANDLE_ERROR;
+}
+
+/**
+ * Appends text to the store's buffer.
+ */
+static void textstore_append(textstore_t *store, char *str, uint32_t len) {
+    if (len + 1 + store->length > store->buffer_cap) {
+        /* Unfortunately, there isn't an aligned_realloc */
+        uint32_t new_capacity= store->buffer_cap * 2;
+        while (new_capacity < len + 1 + store->length) {
+            new_capacity *= 2;
+        }
+        char *new_buffer = aligned_alloc(sizeof(uint32_t), new_capacity);
+        memcpy(new_buffer, store->buffer, store->length);
+        free(store->buffer);
+        store->buffer = new_buffer;
+        store->buffer_cap = new_capacity;
+    }
+    memcpy(&store->buffer[store->length], str, len);
+    store->buffer[store->length + len] = 0;
+    store->length += len + 1;
+}
+
+textstore_handle textstore_intern(textstore_t *store, char *str) {
+    return textstore_intern_len(store, str, strlen(str));
+}
+
+textstore_handle textstore_intern_len(textstore_t *store, char *str, uint32_t len) {
+    textstore_handle handle = to_handle(0, 0);
+    uint32_t index;
+
+    if (len == 0) { /* Special case empty string. */
+        textstore_retain(store, handle);
+        return handle;
+    }
+    if (str == NULL) return TEXTSTORE_HANDLE_ERROR;
+
+    handle = textstore_find(store, str, len);
+    if (handle != TEXTSTORE_HANDLE_ERROR) {
+        textstore_retain(store, handle);
+        return handle;
+    }
+
+    uint32_t offset = store->length;
+    textstore_append(store, str, len);
+
+
+    if (store->available > 0) {
+        /* Pop a freed handle index off the end of the queue. */
+        index = ((uint32_t *)store->buffer)[--store->available];
+        store->generation[index]++;
+    } else {
+        index = store->count++;
+        store->generation[index] = 0;
+    }
+
+    textstore_put(store, str, len, index);
+    handle = to_handle(index, store->generation[index]);
+    store->key[index] = (textstore_slice){offset, len};
+    store->ref[index] = 1;
+    store->active[index] = true;
+
+    if (index > ((store->capacity/4)*3)) {
+        /* At 3/4 capacity, grow the hash-table. */
+        textstore_t copy = *store;
+        textstore_alloc(&copy, copy.capacity * 2);
+        memcpy(copy.key, store->key, copy.count * sizeof(textstore_slice));
+        memcpy(copy.ref, store->ref, copy.count * sizeof(uint32_t));
+        memcpy(copy.generation, store->generation, copy.count * sizeof(uint32_t));
+        memcpy(copy.active, store->active, copy.count * sizeof(bool));
+        copy.capacity *= 2;
+        free(store->map);
+        *store = copy;
+        textstore_rehash(store);
+    }
+
+    return handle;
+}
+
+int textstore_gc(textstore_t *store) {
+    textstore_slice *strings = store->key;
+    uint32_t *refs = store->ref;
+    bool *actives = store->active;
+    uint32_t count = store->count;
+
+    // Pass 1: Count how many strings need to be collected, and determine how
+    //         much space is needed for the new buffer.
+    uint32_t collect = store->available;
+    uint32_t new_length = collect * sizeof(uint32_t);
+    for (uint32_t i = 0; i < count; i++) {
+        if (actives[i]) {
+            if (refs[i] > 0) {
+                new_length += strings[i].len;
+            } else {
+                collect += 1;
+                new_length += sizeof(uint32_t);
+            }
+        }
+    }
+
+    // If no strings are in need of collecting, stop early.
+    if (collect == 0) return 0;
+    
+    // Pass 2: Generate new buffer from the active strings.
+    char *new_buffer = aligned_alloc(alignof(uint32_t), new_length);
+    if (new_buffer == NULL) return 1;
+    memset(new_buffer, 0, new_length);
+    uint32_t new_offset = collect * sizeof(uint32_t);
+    // copy existing free queue to the new one.
+    memcpy(new_buffer, store->buffer, store->available * sizeof(uint32_t));
+    uint32_t *queue_buffer = (uint32_t *)new_buffer;
+    uint32_t queue_offset = store->available;
+
+    // char * text_buffer = (char *)(&queue_buffer[collect]);
+    // uint32_t text_length = new_length - (sizeof(uint32_t) * collect);
+
+    for (uint32_t i = 0; i < count; i++) {
+        if (actives[i]) {
+            if (refs[i] == 0) {
+                queue_buffer[queue_offset++] = i;
+                actives[i] = false;
+                strings[i] = (textstore_slice){0};
+                continue;
+            }
+            memcpy(&new_buffer[new_offset], &store->buffer[strings[i].offset], strings[i].len);
+            strings[i].offset = new_offset;
+            new_offset += strings[i].len + 1;
+        }
+    }
+
+    free(store->buffer);
+    store->buffer = new_buffer;
+    store->available = collect;
+
+    textstore_rehash(store);
+    return 0;
+}
+
+int textstore_init(textstore_t *store, uint32_t initial_buffer) {
+    textstore_t temp = {0};
+    if (initial_buffer == 0) initial_buffer = 1;
+    /* The buffer contains the sequence of available freed handle indexes at the start.
+       Hence, this allocation is aligned to those indexes. */
+    temp.buffer = (char *)aligned_alloc(alignof(uint32_t), initial_buffer);
+    if (temp.buffer == NULL) return 1;
+    temp.buffer_cap = initial_buffer;
+    memset(temp.buffer, 0, initial_buffer);
+
+    temp.capacity = 8;
+    textstore_alloc(&temp, temp.capacity);
+
+    /* Special-case empty string ("") for index 0. */
+    temp.key[0] = (textstore_slice){ 0, 0 };
+    temp.ref[0] = 1;
+    temp.active[0] = true;
+    temp.length++;
+    temp.count++;
+
+    *store = temp;
+    return 0;
+}
+
+void textstore_free(textstore_t *store) {
+    free(store->buffer);
+    free(store->map);
+
+    *store = (textstore_t){0};
+}