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), hasStyles(false) { }
  44         entry(const entry& o) : value(o.value), offset(o.offset),
  45                 hasStyles(o.hasStyles), indices(o.indices),
  46                 configTypeName(o.configTypeName), configs(o.configs) { }
  47
  48         String16 value;
  49         size_t offset;
  50         bool hasStyles;
  51         Vector<size_t> indices;
  52         String8 configTypeName;
  53         Vector<ResTable_config> configs;
  54
  55         String8 makeConfigsString() const;
  56
  57         int compare(const entry& o) const;
  58
  59         inline bool operator<(const entry& o) const { return compare(o) < 0; }
  60         inline bool operator<=(const entry& o) const { return compare(o) <= 0; }
  61         inline bool operator==(const entry& o) const { return compare(o) == 0; }
  62         inline bool operator!=(const entry& o) const { return compare(o) != 0; }
  63         inline bool operator>=(const entry& o) const { return compare(o) >= 0; }
  64         inline bool operator>(const entry& o) const { return compare(o) > 0; }
  65     };
  66
  67     struct entry_style_span {
  68         String16 name;
  69         ResStringPool_span span;
  70     };
  71
  72     struct entry_style {
  73         entry_style() : offset(0) { }
  74
  75         entry_style(const entry_style& o) : offset(o.offset), spans(o.spans) { }
  76
  77         size_t offset;
  78         Vector<entry_style_span> spans;
  79     };
  80
  81     /**
  82      * If 'sorted' is true, then the final strings in the resource data
  83      * structure will be generated in sorted order.  This allow for fast
  84      * lookup with ResStringPool::indexOfString() (O(log n)), at the expense
  85      * of support for styled string entries (which requires the same string
  86      * be included multiple times in the pool).
  87      *
  88      * If 'utf8' is true, strings will be encoded with UTF-8 instead of
  89      * left in Java's native UTF-16.
  90      */
  91     explicit StringPool(bool sorted = false, bool utf8 = false);
  92
  93     /**
  94      * Add a new string to the pool.  If mergeDuplicates is true, thenif
  95      * the string already exists the existing entry for it will be used;
  96      * otherwise, or if the value doesn't already exist, a new entry is
  97      * created.
  98      *
  99      * Returns the index in the entry array of the new string entry.  Note that
 100      * if this string pool is sorted, the returned index will not be valid
 101      * when the pool is finally written.
 102      */
 103     ssize_t add(const String16& value, bool mergeDuplicates = false,
 104             const String8* configTypeName = NULL, const ResTable_config* config = NULL);
 105
 106     ssize_t add(const String16& value, const Vector<entry_style_span>& spans,
 107             const String8* configTypeName = NULL, const ResTable_config* config = NULL);
 108
 109     ssize_t add(const String16& ident, const String16& value,
 110                 bool mergeDuplicates = false,
 111                 const String8* configTypeName = NULL, const ResTable_config* config = NULL);
 112
 113     status_t addStyleSpan(size_t idx, const String16& name,
 114                           uint32_t start, uint32_t end);
 115     status_t addStyleSpans(size_t idx, const Vector<entry_style_span>& spans);
 116     status_t addStyleSpan(size_t idx, const entry_style_span& span);
 117
 118     size_t size() const;
 119
 120     const entry& entryAt(size_t idx) const;
 121
 122     size_t countIdentifiers() const;
 123
 124     // Sort the contents of the string block by the configuration associated
 125     // with each item.  After doing this you can use mapOriginalPosToNewPos()
 126     // to find out the new position given the position originall returned by
 127     // add().
 128     void sortByConfig();
 129
 130     // For use after sortByConfig() to map from the original position of
 131     // a string to its new sorted position.
 132     size_t mapOriginalPosToNewPos(size_t originalPos) const {
 133         return mOriginalPosToNewPos.itemAt(originalPos);
 134     }
 135
 136     sp<AaptFile> createStringBlock();
 137
 138     status_t writeStringBlock(const sp<AaptFile>& pool);
 139
 140     /**
 141      * Find out an offset in the pool for a particular string.  If the string
 142      * pool is sorted, this can not be called until after createStringBlock()
 143      * or writeStringBlock() has been called
 144      * (which determines the offsets).  In the case of a string that appears
 145      * multiple times in the pool, the first offset will be returned.  Returns
 146      * -1 if the string does not exist.
 147      */
 148     ssize_t offsetForString(const String16& val) const;
 149
 150     /**
 151      * Find all of the offsets in the pool for a particular string.  If the
 152      * string pool is sorted, this can not be called until after
 153      * createStringBlock() or writeStringBlock() has been called
 154      * (which determines the offsets).  Returns NULL if the string does not exist.
 155      */
 156     const Vector<size_t>* offsetsForString(const String16& val) const;
 157
 158 private:
 159     static int config_sort(const size_t* lhs, const size_t* rhs, void* state);
 160
 161     const bool                              mSorted;
 162     const bool                              mUTF8;
 163
 164     // The following data structures represent the actual structures
 165     // that will be generated for the final string pool.
 166
 167     // Raw array of unique strings, in some arbitrary order.  This is the
 168     // actual strings that appear in the final string pool, in the order
 169     // that they will be written.
 170     Vector<entry>                           mEntries;
 171     // Array of indices into mEntries, in the order they were
 172     // added to the pool.  This can be different than mEntries
 173     // if the same string was added multiple times (it will appear
 174     // once in mEntries, with multiple occurrences in this array).
 175     // This is the lookup array that will be written for finding
 176     // the string for each offset/position in the string pool.
 177     Vector<size_t>                          mEntryArray;
 178     // Optional style span information associated with each index of
 179     // mEntryArray.
 180     Vector<entry_style>                     mEntryStyleArray;
 181
 182     // The following data structures are used for book-keeping as the
 183     // string pool is constructed.
 184
 185     // Unique set of all the strings added to the pool, mapped to
 186     // the first index of mEntryArray where the value was added.
 187     DefaultKeyedVector<String16, ssize_t>   mValues;
 188     // Unique set of all (optional) identifiers of strings in the
 189     // pool, mapping to indices in mEntries.
 190     DefaultKeyedVector<String16, ssize_t>   mIdents;
 191     // This array maps from the original position a string was placed at
 192     // in mEntryArray to its new position after being sorted with sortByConfig().
 193     Vector<size_t>                          mOriginalPosToNewPos;
 194 };
 195
 196 #endif
 197