options/glibc: Add the hsearch_r family of functions

options/glibc/generic/search.cpp

@@ -0,0 +1,142 @@
+#include <bits/glibc/glibc_search.h>
+#include <stdlib.h>
+#include <string.h>
+
+// This code was lifted from musl!
+
+#define MINSIZE 8
+#define MAXSIZE ((size_t)-1/2 + 1)
+
+struct _ENTRY {
+	ENTRY *entries;
+	size_t mask;
+	size_t used;
+};
+
+static struct hsearch_data htab;
+
+static size_t keyhash(char *k) {
+	unsigned char *p = (unsigned char *)k;
+	size_t h = 0;
+
+	while(*p) {
+		h = 31 * h + *p++;
+	}
+	return h;
+}
+
+static int resize(size_t nel, struct hsearch_data *htab) {
+	size_t newsize;
+	size_t i, j;
+	size_t oldsize = htab->table->mask + 1;
+	ENTRY *e, *newe;
+	ENTRY *oldtab = htab->table->entries;
+
+	if(nel > MAXSIZE) {
+		nel = MAXSIZE;
+	}
+
+	for(newsize = MINSIZE; newsize < nel; newsize *= 2);
+
+	htab->table->entries = (ENTRY *)calloc(newsize, sizeof *htab->table->entries);
+
+	if(!htab->table->entries) {
+		htab->table->entries = oldtab;
+		return 0;
+	}
+	htab->table->mask = newsize - 1;
+
+	if(!oldtab)
+		return 1;
+
+	for(e = oldtab; e < oldtab + oldsize; e++) {
+		if(e->key) {
+			for(i = keyhash(e->key),j = 1; ; i += j++) {
+				newe = htab->table->entries + (i & htab->table->mask);
+				if(!newe->key) {
+					break;
+				}
+			}
+			*newe = *e;
+		}
+	}
+	free(oldtab);
+	return 1;
+}
+
+static ENTRY *lookup(char *key, size_t hash, struct hsearch_data *htab) {
+	size_t i, j;
+	ENTRY *e;
+
+	for(i = hash, j = 1; ; i += j++) {
+		e = htab->table->entries + (i & htab->table->mask);
+		if(!e->key || strcmp(e->key, key) == 0) {
+			break;
+		}
+	}
+	return e;
+}
+
+int hsearch_r(ENTRY item, ACTION action, ENTRY **retval, struct hsearch_data *htab) {
+	size_t hash = keyhash(item.key);
+	ENTRY *e = lookup(item.key, hash, htab);
+
+	if(e->key) {
+		*retval = e;
+		return 1;
+	}
+	if(action == FIND) {
+		*retval = 0;
+		return 0;
+	}
+	*e = item;
+	if(++htab->table->used > htab->table->mask - htab->table->mask / 4) {
+		if(!resize(2 * htab->table->used, htab)) {
+			htab->table->used--;
+			e->key = 0;
+			*retval = 0;
+			return 0;
+		}
+		e = lookup(item.key, hash, htab);
+	}
+	*retval = e;
+	return 1;
+}
+
+int hcreate_r(size_t nel, struct hsearch_data *htab) {
+	int r;
+
+	htab->table = (_ENTRY *)calloc(1, sizeof *htab->table);
+	if(!htab->table) {
+		return 0;
+	}
+	r = resize(nel, htab);
+	if(r == 0) {
+		free(htab->table);
+		htab->table = 0;
+	}
+	return r;
+}
+
+void hdestroy_r(struct hsearch_data *htab) {
+	if(htab->table) {
+		free(htab->table->entries);
+	}
+	free(htab->table);
+	htab->table = 0;
+}
+
+int hcreate(size_t nel) {
+	return hcreate_r(nel, &htab);
+}
+
+void hdestroy(void) {
+	hdestroy_r(&htab);
+}
+
+ENTRY *hsearch(ENTRY item, ACTION action) {
+	ENTRY *e;
+
+	hsearch_r(item, action, &e, &htab);
+	return e;
+}

options/glibc/include/bits/glibc/glibc_search.h

@@ -0,0 +1,44 @@
+#ifndef _GLIBC_SEARCH_H
+#define _GLIBC_SEARCH_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include <bits/size_t.h>
+
+typedef enum {
+	FIND,
+	ENTER
+} ACTION;
+
+typedef struct entry {
+	char *key;
+	void *data;
+} ENTRY;
+
+struct _ENTRY;
+
+struct hsearch_data {
+	struct _ENTRY *table;
+	unsigned int size;
+	unsigned int filled;
+};
+
+#ifndef __MLIBC_ABI_ONLY
+
+int hcreate(size_t nel);
+void hdestroy(void);
+ENTRY *hsearch(ENTRY item, ACTION action);
+
+int hsearch_r(ENTRY item, ACTION action, ENTRY **ret, struct hsearch_data *htab);
+int hcreate_r(size_t num_elements, struct hsearch_data *htab);
+void hdestroy_r(struct hsearch_data *htab);
+
+#endif
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* _GLIBC_SEARCH_H */

options/glibc/meson.build

@@ -19,6 +19,7 @@ libc_sources += files(
 	'generic/glibc-assert.cpp',
 	'generic/malloc.cpp',
 	'generic/sys-io.cpp',
+	'generic/search.cpp',
 )
 
 if not no_headers
@@ -84,6 +85,7 @@ if not no_headers
 		'include/bits/glibc/glibc_signal.h',
 		'include/bits/glibc/glibc_assert.h',
 		'include/bits/glibc/glibc_malloc.h',
+		'include/bits/glibc/glibc_search.h',
 		subdir: 'bits/glibc'
 	)
 endif

options/posix/include/search.h

@@ -3,6 +3,7 @@
 #define _SEARCH_H
 
 #include <stddef.h>
+#include <mlibc-config.h>
 
 #ifdef __cplusplus
 extern "C" {
@@ -15,6 +16,10 @@ typedef enum {
   leaf
 } VISIT;
 
+#if __MLIBC_GLIBC_OPTION
+#include <bits/glibc/glibc_search.h>
+#endif
+
 #ifndef __MLIBC_ABI_ONLY
 
 void *tsearch(const void *, void **, int(*compar)(const void *, const void *));