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-rw-r--r--utils/perfect_hash.cc37
1 files changed, 37 insertions, 0 deletions
diff --git a/utils/perfect_hash.cc b/utils/perfect_hash.cc
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+++ b/utils/perfect_hash.cc
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+#include "config.h"
+
+#ifdef HAVE_CMPH
+
+#include "perfect_hash.h"
+
+#include <cstdio>
+#include <iostream>
+
+using namespace std;
+
+PerfectHashFunction::~PerfectHashFunction() {
+ cmph_destroy(mphf_);
+}
+
+PerfectHashFunction::PerfectHashFunction(const string& fname) {
+ FILE* f = fopen(fname.c_str(), "r");
+ if (!f) {
+ cerr << "Failed to open file " << fname << " for reading: cannot load hash function.\n";
+ abort();
+ }
+ mphf_ = cmph_load(f);
+ if (!mphf_) {
+ cerr << "cmph_load failed on " << fname << "!\n";
+ abort();
+ }
+}
+
+size_t PerfectHashFunction::operator()(const string& key) const {
+ return cmph_search(mphf_, &key[0], key.size());
+}
+
+size_t PerfectHashFunction::number_of_keys() const {
+ return cmph_size(mphf_);
+}
+
+#endif