From: John Darrington Date: Fri, 20 Aug 2010 16:49:01 +0000 (+0200) Subject: file-handle-def.c: replace hash with hmap X-Git-Tag: v0.7.6~282 X-Git-Url: https://pintos-os.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=58d0bff829516ccbc159857674e61e813962b1d8;p=pspp-builds.git file-handle-def.c: replace hash with hmap --- diff --git a/src/data/file-handle-def.c b/src/data/file-handle-def.c index 6ed3f8f9..beba83d4 100644 --- a/src/data/file-handle-def.c +++ b/src/data/file-handle-def.c @@ -1,5 +1,5 @@ /* PSPP - a program for statistical analysis. - Copyright (C) 1997-9, 2000, 2006, 2009 Free Software Foundation, Inc. + Copyright (C) 1997-9, 2000, 2006, 2009, 2010 Free Software Foundation, Inc. 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 @@ -24,10 +24,11 @@ #include #include -#include +#include #include #include #include +#include #include #include #include @@ -80,6 +81,9 @@ static struct file_handle *create_handle (const char *id, static void free_handle (struct file_handle *); static void unname_handle (struct file_handle *); +/* Hash table of all active locks. */ +static struct hmap locks = HMAP_INITIALIZER (locks); + /* File handle initialization routine. */ void fh_init (void) @@ -373,6 +377,8 @@ fh_set_default_handle (struct file_handle *new_default_handle) /* Information about a file handle's readers or writers. */ struct fh_lock { + struct hmap_node node; /* hmap_node member. */ + /* Hash key. */ enum fh_referent referent; /* Type of underlying file. */ union @@ -392,14 +398,12 @@ struct fh_lock void *aux; /* Owner's auxiliary data. */ }; -/* Hash table of all active locks. */ -static struct hsh_table *locks; static void make_key (struct fh_lock *, const struct file_handle *, enum fh_access); static void free_key (struct fh_lock *); -static int compare_fh_locks (const void *, const void *, const void *); -static unsigned int hash_fh_lock (const void *, const void *); +static int compare_fh_locks (const struct fh_lock *a, const struct fh_lock *b); +static unsigned int hash_fh_lock (const struct fh_lock *lock); /* Tries to lock handle H for the given kind of ACCESS and TYPE of file. Returns a pointer to a struct fh_lock if successful, @@ -431,31 +435,36 @@ struct fh_lock * fh_lock (struct file_handle *h, enum fh_referent mask UNUSED, const char *type, enum fh_access access, bool exclusive) { - struct fh_lock key, *lock; - void **lockp; + struct fh_lock *key = NULL; + size_t hash ; + struct fh_lock *lock = NULL; + bool found_lock = false; assert ((fh_get_referent (h) & mask) != 0); assert (access == FH_ACC_READ || access == FH_ACC_WRITE); - if (locks == NULL) - locks = hsh_create (0, compare_fh_locks, hash_fh_lock, NULL, NULL); + key = xmalloc (sizeof *key); + + make_key (key, h, access); + + key->open_cnt = 1; + key->exclusive = exclusive; + key->type = type; + key->aux = NULL; - make_key (&key, h, access); - lockp = hsh_probe (locks, &key); - if (*lockp == NULL) + hash = hash_fh_lock (key); + + HMAP_FOR_EACH_WITH_HASH (lock, struct fh_lock, node, hash, &locks) { - lock = *lockp = xmalloc (sizeof *lock); - *lock = key; - lock->open_cnt = 1; - lock->exclusive = exclusive; - lock->type = type; - lock->aux = NULL; + if ( 0 == compare_fh_locks (lock, key)) + { + found_lock = true; + break; + } } - else - { - free_key (&key); - lock = *lockp; + if ( found_lock ) + { if (strcmp (lock->type, type)) { if (access == FH_ACC_READ) @@ -475,9 +484,27 @@ fh_lock (struct file_handle *h, enum fh_referent mask UNUSED, return NULL; } lock->open_cnt++; + + free_key (key); + free (key); + + return lock; } - return lock; + hmap_insert (&locks, &key->node, hash); + found_lock = false; + HMAP_FOR_EACH_WITH_HASH (lock, struct fh_lock, node, hash, &locks) + { + if ( 0 == compare_fh_locks (lock, key)) + { + found_lock = true; + break; + } + } + + assert (found_lock); + + return key; } /* Releases LOCK that was acquired with fh_lock. @@ -499,7 +526,7 @@ fh_unlock (struct fh_lock *lock) assert (lock->open_cnt > 0); if (--lock->open_cnt == 0) { - hsh_delete (locks, lock); + hmap_delete (&locks, &lock->node); free_key (lock); free (lock); return false; @@ -532,10 +559,24 @@ bool fh_is_locked (const struct file_handle *handle, enum fh_access access) { struct fh_lock key; - bool is_locked; + const struct fh_lock *k = NULL; + bool is_locked = false; + size_t hash ; make_key (&key, handle, access); - is_locked = hsh_find (locks, &key) != NULL; + + hash = hash_fh_lock (&key); + + + HMAP_FOR_EACH_WITH_HASH (k, struct fh_lock, node, hash, &locks) + { + if ( 0 == compare_fh_locks (k, &key)) + { + is_locked = true; + break; + } + } + free_key (&key); return is_locked; @@ -569,11 +610,8 @@ free_key (struct fh_lock *lock) /* Compares the key fields in struct fh_lock objects A and B and returns a strcmp()-type result. */ static int -compare_fh_locks (const void *a_, const void *b_, const void *aux UNUSED) +compare_fh_locks (const struct fh_lock *a, const struct fh_lock *b) { - const struct fh_lock *a = a_; - const struct fh_lock *b = b_; - if (a->referent != b->referent) return a->referent < b->referent ? -1 : 1; else if (a->access != b->access) @@ -589,9 +627,8 @@ compare_fh_locks (const void *a_, const void *b_, const void *aux UNUSED) /* Returns a hash value for LOCK. */ static unsigned int -hash_fh_lock (const void *lock_, const void *aux UNUSED) +hash_fh_lock (const struct fh_lock *lock) { - const struct fh_lock *lock = lock_; unsigned int basis; if (lock->referent == FH_REF_FILE) basis = fn_hash_identity (lock->u.file);