StringPool.h

   1 //
   2 // Copyright 2006 The Android Open Source Project
   3 //
   4 // Build resource files from raw assets.
   5 //
   6
   7 #ifndef STRING_POOL_H
   8 #define STRING_POOL_H
   9
  10 #include "Main.h"
  11 #include "AaptAssets.h"
  12
  13 #include <utils/ResourceTypes.h>
  14 #include <utils/String16.h>
  15 #include <utils/TextOutput.h>
  16
  17 #include <sys/types.h>
  18 #include <sys/stat.h>
  19 #include <fcntl.h>
  20 #include <ctype.h>
  21 #include <errno.h>
  22
  23 #include <expat.h>
  24
  25 using namespace android;
  26
  27 #define PRINT_STRING_METRICS 0
  28
  29 void strcpy16_htod(uint16_t* dst, const uint16_t* src);
  30
  31 void printStringPool(const ResStringPool* pool);
  32
  33 /**
  34  * The StringPool class is used as an intermediate representation for
  35  * generating the string pool resource data structure that can be parsed with
  36  * ResStringPool in include/utils/ResourceTypes.h.
  37  */
  38 class StringPool
  39 {
  40 public:
  41     struct entry {
  42         entry() : offset(0) { }
  43         entry(const String16& _value) : value(_value), offset(0) { }
  44         entry(const entry& o) : value(o.value), offset(o.offset), indices(o.indices) { }
  45
  46         String16 value;
  47         size_t offset;
  48         Vector<size_t> indices;
  49     };
  50
  51     struct entry_style_span {
  52         String16 name;
  53         ResStringPool_span span;
  54     };
  55
  56     struct entry_style {
  57         entry_style() : offset(0) { }
  58
  59         entry_style(const entry_style& o) : offset(o.offset), spans(o.spans) { }
  60
  61         size_t offset;
  62         Vector<entry_style_span> spans;
  63     };
  64
  65     /**
  66      * If 'sorted' is true, then the final strings in the resource data
  67      * structure will be generated in sorted order.  This allow for fast
  68      * lookup with ResStringPool::indexOfString() (O(log n)), at the expense
  69      * of support for styled string entries (which requires the same string
  70      * be included multiple times in the pool).
  71      */
  72     explicit StringPool(bool sorted = false);
  73
  74     /**
  75      * Add a new string to the pool.  If mergeDuplicates is true, thenif
  76      * the string already exists the existing entry for it will be used;
  77      * otherwise, or if the value doesn't already exist, a new entry is
  78      * created.
  79      *
  80      * Returns the index in the entry array of the new string entry.  Note that
  81      * if this string pool is sorted, the returned index will not be valid
  82      * when the pool is finally written.
  83      */
  84     ssize_t add(const String16& value, bool mergeDuplicates = false);
  85
  86     ssize_t add(const String16& value, const Vector<entry_style_span>& spans);
  87
  88     ssize_t add(const String16& ident, const String16& value,
  89                 bool mergeDuplicates = false);
  90
  91     status_t addStyleSpan(size_t idx, const String16& name,
  92                           uint32_t start, uint32_t end);
  93     status_t addStyleSpans(size_t idx, const Vector<entry_style_span>& spans);
  94     status_t addStyleSpan(size_t idx, const entry_style_span& span);
  95
  96     size_t size() const;
  97
  98     const entry& entryAt(size_t idx) const;
  99
 100     size_t countIdentifiers() const;
 101
 102     sp<AaptFile> createStringBlock();
 103
 104     status_t writeStringBlock(const sp<AaptFile>& pool);
 105
 106     /**
 107      * Find out an offset in the pool for a particular string.  If the string
 108      * pool is sorted, this can not be called until after createStringBlock()
 109      * or writeStringBlock() has been called
 110      * (which determines the offsets).  In the case of a string that appears
 111      * multiple times in the pool, the first offset will be returned.  Returns
 112      * -1 if the string does not exist.
 113      */
 114     ssize_t offsetForString(const String16& val) const;
 115
 116     /**
 117      * Find all of the offsets in the pool for a particular string.  If the
 118      * string pool is sorted, this can not be called until after
 119      * createStringBlock() or writeStringBlock() has been called
 120      * (which determines the offsets).  Returns NULL if the string does not exist.
 121      */
 122     const Vector<size_t>* offsetsForString(const String16& val) const;
 123
 124 private:
 125     const bool                              mSorted;
 126     // Raw array of unique strings, in some arbitrary order.
 127     Vector<entry>                           mEntries;
 128     // Array of indices into mEntries, in the order they were
 129     // added to the pool.  This can be different than mEntries
 130     // if the same string was added multiple times (it will appear
 131     // once in mEntries, with multiple occurrences in this array).
 132     Vector<size_t>                          mEntryArray;
 133     // Optional style span information associated with each index of
 134     // mEntryArray.
 135     Vector<entry_style>                     mEntryStyleArray;
 136     // Mapping from indices in mEntryArray to indices in mValues.
 137     Vector<size_t>                          mEntryArrayToValues;
 138     // Unique set of all the strings added to the pool, mapped to
 139     // the first index of mEntryArray where the value was added.
 140     DefaultKeyedVector<String16, ssize_t>   mValues;
 141     // Unique set of all (optional) identifiers of strings in the
 142     // pool, mapping to indices in mEntries.
 143     DefaultKeyedVector<String16, ssize_t>   mIdents;
 144
 145 };
 146
 147 #endif
 148