StringPool.h revision 8a9cfcc85260eadcc2c17c4a8911c6d93b642f39 
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 <androidfw/ResourceTypes.h>
14#include <utils/String16.h>
15#include <utils/TextOutput.h>
16#include <utils/TypeHelpers.h>
17
18#include <sys/types.h>
19#include <sys/stat.h>
20#include <fcntl.h>
21#include <ctype.h>
22#include <errno.h>
23
24#include <expat.h>
25
26using namespace android;
27
28#define PRINT_STRING_METRICS 0
29
30void strcpy16_htod(uint16_t* dst, const uint16_t* src);
31
32void printStringPool(const ResStringPool* pool);
33
34/**
35 * The StringPool class is used as an intermediate representation for
36 * generating the string pool resource data structure that can be parsed with
37 * ResStringPool in include/utils/ResourceTypes.h.
38 */
39class StringPool
40{
41public:
42    struct entry {
43        entry() : offset(0) { }
44        entry(const String16& _value) : value(_value), offset(0), hasStyles(false) { }
45        entry(const entry& o) : value(o.value), offset(o.offset),
46                hasStyles(o.hasStyles), indices(o.indices),
47                configTypeName(o.configTypeName), configs(o.configs) { }
48
49        String16 value;
50        size_t offset;
51        bool hasStyles;
52        Vector<size_t> indices;
53        String8 configTypeName;
54        Vector<ResTable_config> configs;
55
56        String8 makeConfigsString() const;
57
58        int compare(const entry& o) const;
59
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        inline bool operator>(const entry& o) const { return compare(o) > 0; }
66    };
67
68    struct entry_style_span {
69        String16 name;
70        ResStringPool_span span;
71    };
72
73    struct entry_style {
74        entry_style() : offset(0) { }
75
76        entry_style(const entry_style& o) : offset(o.offset), spans(o.spans) { }
77
78        size_t offset;
79        Vector<entry_style_span> spans;
80    };
81
82    /**
83     * If 'sorted' is true, then the final strings in the resource data
84     * structure will be generated in sorted order.  This allow for fast
85     * lookup with ResStringPool::indexOfString() (O(log n)), at the expense
86     * of support for styled string entries (which requires the same string
87     * be included multiple times in the pool).
88     *
89     * If 'utf8' is true, strings will be encoded with UTF-8 instead of
90     * left in Java's native UTF-16.
91     */
92    explicit StringPool(bool sorted = false, bool utf8 = false);
93
94    /**
95     * Add a new string to the pool.  If mergeDuplicates is true, thenif
96     * the string already exists the existing entry for it will be used;
97     * otherwise, or if the value doesn't already exist, a new entry is
98     * created.
99     *
100     * Returns the index in the entry array of the new string entry.  Note that
101     * if this string pool is sorted, the returned index will not be valid
102     * when the pool is finally written.
103     */
104    ssize_t add(const String16& value, bool mergeDuplicates = false,
105            const String8* configTypeName = NULL, const ResTable_config* config = NULL);
106
107    ssize_t add(const String16& value, const Vector<entry_style_span>& spans,
108            const String8* configTypeName = NULL, const ResTable_config* config = NULL);
109
110    ssize_t add(const String16& ident, const String16& value,
111                bool mergeDuplicates = false,
112                const String8* configTypeName = NULL, const ResTable_config* config = NULL);
113
114    status_t addStyleSpan(size_t idx, const String16& name,
115                          uint32_t start, uint32_t end);
116    status_t addStyleSpans(size_t idx, const Vector<entry_style_span>& spans);
117    status_t addStyleSpan(size_t idx, const entry_style_span& span);
118
119    size_t size() const;
120
121    const entry& entryAt(size_t idx) const;
122
123    size_t countIdentifiers() const;
124
125    // Sort the contents of the string block by the configuration associated
126    // with each item.  After doing this you can use mapOriginalPosToNewPos()
127    // to find out the new position given the position originall returned by
128    // add().
129    void sortByConfig();
130
131    // For use after sortByConfig() to map from the original position of
132    // a string to its new sorted position.
133    size_t mapOriginalPosToNewPos(size_t originalPos) const {
134        return mOriginalPosToNewPos.itemAt(originalPos);
135    }
136
137    sp<AaptFile> createStringBlock();
138
139    status_t writeStringBlock(const sp<AaptFile>& pool);
140
141    /**
142     * Find out an offset in the pool for a particular string.  If the string
143     * pool is sorted, this can not be called until after createStringBlock()
144     * or writeStringBlock() has been called
145     * (which determines the offsets).  In the case of a string that appears
146     * multiple times in the pool, the first offset will be returned.  Returns
147     * -1 if the string does not exist.
148     */
149    ssize_t offsetForString(const String16& val) const;
150
151    /**
152     * Find all of the offsets in the pool for a particular string.  If the
153     * string pool is sorted, this can not be called until after
154     * createStringBlock() or writeStringBlock() has been called
155     * (which determines the offsets).  Returns NULL if the string does not exist.
156     */
157    const Vector<size_t>* offsetsForString(const String16& val) const;
158
159private:
160    static int config_sort(const size_t* lhs, const size_t* rhs, void* state);
161
162    const bool                              mSorted;
163    const bool                              mUTF8;
164
165    // The following data structures represent the actual structures
166    // that will be generated for the final string pool.
167
168    // Raw array of unique strings, in some arbitrary order.  This is the
169    // actual strings that appear in the final string pool, in the order
170    // that they will be written.
171    Vector<entry>                           mEntries;
172    // Array of indices into mEntries, in the order they were
173    // added to the pool.  This can be different than mEntries
174    // if the same string was added multiple times (it will appear
175    // once in mEntries, with multiple occurrences in this array).
176    // This is the lookup array that will be written for finding
177    // the string for each offset/position in the string pool.
178    Vector<size_t>                          mEntryArray;
179    // Optional style span information associated with each index of
180    // mEntryArray.
181    Vector<entry_style>                     mEntryStyleArray;
182
183    // The following data structures are used for book-keeping as the
184    // string pool is constructed.
185
186    // Unique set of all the strings added to the pool, mapped to
187    // the first index of mEntryArray where the value was added.
188    DefaultKeyedVector<String16, ssize_t>   mValues;
189    // Unique set of all (optional) identifiers of strings in the
190    // pool, mapping to indices in mEntries.
191    DefaultKeyedVector<String16, ssize_t>   mIdents;
192    // This array maps from the original position a string was placed at
193    // in mEntryArray to its new position after being sorted with sortByConfig().
194    Vector<size_t>                          mOriginalPosToNewPos;
195};
196
197// The entry types are trivially movable because all fields they contain, including
198// the vectors and strings, are trivially movable.
199namespace android {
200    ANDROID_TRIVIAL_MOVE_TRAIT(StringPool::entry);
201    ANDROID_TRIVIAL_MOVE_TRAIT(StringPool::entry_style_span);
202    ANDROID_TRIVIAL_MOVE_TRAIT(StringPool::entry_style);
203};
204
205#endif
206
207