NameToCharCode: remove custom hashmap

Using std::unordered_map makes the code quite a bit simpler

2 files changed, 15 insertions, 107 deletions

diff --git a/poppler/NameToCharCode.cc b/poppler/NameToCharCode.cc
index 73c9f1c1..78aa6bee 100644
--- a/poppler/NameToCharCode.cc
+++ b/poppler/NameToCharCode.cc
@@ -23,110 +23,18 @@
 #include <config.h>
 
 #include <cstring>
-#include "goo/gmem.h"
 #include "NameToCharCode.h"
 
-//------------------------------------------------------------------------
-
-struct NameToCharCodeEntry
-{
-    char *name;
-    CharCode c;
-};
-
-//------------------------------------------------------------------------
-
-NameToCharCode::NameToCharCode()
-{
-    int i;
-
-    size = 31;
-    len = 0;
-    tab = (NameToCharCodeEntry *)gmallocn(size, sizeof(NameToCharCodeEntry));
-    for (i = 0; i < size; ++i) {
-        tab[i].name = nullptr;
-    }
-}
-
-NameToCharCode::~NameToCharCode()
-{
-    int i;
-
-    for (i = 0; i < size; ++i) {
-        if (tab[i].name) {
-            gfree(tab[i].name);
-        }
-    }
-    gfree(tab);
-}
-
 void NameToCharCode::add(const char *name, CharCode c)
 {
-    NameToCharCodeEntry *oldTab;
-    int h, i, oldSize;
-
-    // expand the table if necessary
-    if (len >= size / 2) {
-        oldSize = size;
-        oldTab = tab;
-        size = 2 * size + 1;
-        tab = (NameToCharCodeEntry *)gmallocn(size, sizeof(NameToCharCodeEntry));
-        for (h = 0; h < size; ++h) {
-            tab[h].name = nullptr;
-        }
-        for (i = 0; i < oldSize; ++i) {
-            if (oldTab[i].name) {
-                h = hash(oldTab[i].name);
-                while (tab[h].name) {
-                    if (++h == size) {
-                        h = 0;
-                    }
-                }
-                tab[h] = oldTab[i];
-            }
-        }
-        gfree(oldTab);
-    }
-
-    // add the new name
-    h = hash(name);
-    while (tab[h].name && (strcmp(tab[h].name, name) != 0)) {
-        if (++h == size) {
-            h = 0;
-        }
-    }
-    if (!tab[h].name) {
-        tab[h].name = copyString(name);
-    }
-    tab[h].c = c;
-
-    ++len;
+    tab.insert_or_assign(std::string { name }, c);
 }
 
 CharCode NameToCharCode::lookup(const char *name) const
 {
-    int h;
-
-    h = hash(name);
-    while (tab[h].name) {
-        if (!strcmp(tab[h].name, name)) {
-            return tab[h].c;
-        }
-        if (++h == size) {
-            h = 0;
-        }
+    auto it = tab.find(name);
+    if (it != tab.end()) {
+        return it->second;
     }
     return 0;
 }
-
-int NameToCharCode::hash(const char *name) const
-{
-    const char *p;
-    unsigned int h;
-
-    h = 0;
-    for (p = name; *p; ++p) {
-        h = 17 * h + (int)(*p & 0xff);
-    }
-    return (int)(h % size);
-}
diff --git a/poppler/NameToCharCode.h b/poppler/NameToCharCode.h
index 53b8972e..3b74e354 100644
--- a/poppler/NameToCharCode.h
+++ b/poppler/NameToCharCode.h
@@ -24,6 +24,8 @@
 #define NAMETOCHARCODE_H
 
 #include "CharTypes.h"
+#include <unordered_map>
+#include <string>
 
 struct NameToCharCodeEntry;
 
@@ -32,21 +34,19 @@ struct NameToCharCodeEntry;
 class NameToCharCode
 {
 public:
-    NameToCharCode();
-    ~NameToCharCode();
-
-    NameToCharCode(const NameToCharCode &) = delete;
-    NameToCharCode &operator=(const NameToCharCode &) = delete;
-
     void add(const char *name, CharCode c);
     CharCode lookup(const char *name) const;
 
 private:
-    int hash(const char *name) const;
-
-    NameToCharCodeEntry *tab;
-    int size;
-    int len;
+    /*This is a helper struct to allow looking up by char* into a std string unordered_map*/
+    struct string_hasher
+    {
+        using is_transparent = void;
+        [[nodiscard]] size_t operator()(const char *txt) const { return std::hash<std::string_view> {}(txt); }
+        [[nodiscard]] size_t operator()(const std::string &txt) const { return std::hash<std::string> {}(txt); }
+    };
+
+    std::unordered_map<std::string, CharCode, string_hasher, std::equal_to<>> tab;
 };
 
 #endif