uint32_t ResTable::identifierForName()

in libresource/ResourceTypes.cpp [4253:4406]

• 135 lines of code
• 41 McCabe index (conditional complexity)

uint32_t ResTable::identifierForName(const char16_t* name, size_t nameLen,
                                     const char16_t* type, size_t typeLen,
                                     const char16_t* package,
                                     size_t packageLen,
                                     uint32_t* outTypeSpecFlags) const
{
    if (kDebugTableSuperNoisy) {
        printf("Identifier for name: error=%d\n", mError);
    }

    // Check for internal resource identifier as the very first thing, so
    // that we will always find them even when there are no resources.
    if (name[0] == '^') {
        const int N = (sizeof(ID_NAMES)/sizeof(ID_NAMES[0]));
        size_t len;
        for (int i=0; i<N; i++) {
            const id_name_map* m = ID_NAMES + i;
            len = m->len;
            if (len != nameLen) {
                continue;
            }
            for (size_t j=1; j<len; j++) {
                if (m->name[j] != name[j]) {
                    goto nope;
                }
            }
            if (outTypeSpecFlags) {
                *outTypeSpecFlags = ResTable_typeSpec::SPEC_PUBLIC;
            }
            return m->id;
nope:
            ;
        }
        if (nameLen > 7) {
            if (name[1] == 'i' && name[2] == 'n'
                && name[3] == 'd' && name[4] == 'e' && name[5] == 'x'
                && name[6] == '_') {
                int index = atoi(String8(name + 7, nameLen - 7).string());
                if (Res_CHECKID(index)) {
                    ALOGW("Array resource index: %d is too large.",
                         index);
                    return 0;
                }
                if (outTypeSpecFlags) {
                    *outTypeSpecFlags = ResTable_typeSpec::SPEC_PUBLIC;
                }
                return  Res_MAKEARRAY(index);
            }
        }
        return 0;
    }

    if (mError != NO_ERROR) {
        return 0;
    }

    bool fakePublic = false;

    // Figure out the package and type we are looking in...

    const char16_t* packageEnd = NULL;
    const char16_t* typeEnd = NULL;
    const char16_t* const nameEnd = name+nameLen;
    const char16_t* p = name;
    while (p < nameEnd) {
        if (*p == ':') packageEnd = p;
        else if (*p == '/') typeEnd = p;
        p++;
    }
    if (*name == '@') {
        name++;
        if (*name == '*') {
            fakePublic = true;
            name++;
        }
    }
    if (name >= nameEnd) {
        return 0;
    }

    if (packageEnd) {
        package = name;
        packageLen = packageEnd-name;
        name = packageEnd+1;
    } else if (!package) {
        return 0;
    }

    if (typeEnd) {
        type = name;
        typeLen = typeEnd-name;
        name = typeEnd+1;
    } else if (!type) {
        return 0;
    }

    if (name >= nameEnd) {
        return 0;
    }
    nameLen = nameEnd-name;

    if (kDebugTableNoisy) {
        printf("Looking for identifier: type=%s, name=%s, package=%s\n",
                String8(type, typeLen).string(),
                String8(name, nameLen).string(),
                String8(package, packageLen).string());
    }

    const String16 attr("attr");
    const String16 attrPrivate("^attr-private");

    const size_t NG = mPackageGroups.size();
    for (size_t ig=0; ig<NG; ig++) {
        const PackageGroup* group = mPackageGroups[ig];

        if (strzcmp16(package, packageLen,
                      group->name.string(), group->name.size())) {
            if (kDebugTableNoisy) {
                printf("Skipping package group: %s\n", String8(group->name).string());
            }
            continue;
        }

        const size_t packageCount = group->packages.size();
        for (size_t pi = 0; pi < packageCount; pi++) {
            const char16_t* targetType = type;
            size_t targetTypeLen = typeLen;

            do {
                ssize_t ti = group->packages[pi]->typeStrings.indexOfString(
                        targetType, targetTypeLen);
                if (ti < 0) {
                    continue;
                }

                ti += group->packages[pi]->typeIdOffset;

                const uint32_t identifier = findEntry(group, ti, name, nameLen,
                        outTypeSpecFlags);
                if (identifier != 0) {
                    if (fakePublic && outTypeSpecFlags) {
                        *outTypeSpecFlags |= ResTable_typeSpec::SPEC_PUBLIC;
                    }
                    return identifier;
                }
            } while (strzcmp16(attr.string(), attr.size(), targetType, targetTypeLen) == 0
                    && (targetType = attrPrivate.string())
                    && (targetTypeLen = attrPrivate.size())
            );
        }
        break;
    }
    return 0;
}