Move Codec2-related code from hardware/google/av

Test: None
Bug: 112362730
Change-Id: Ie2f8ff431d65c40333f267ab9877d47089adeea4
diff --git a/media/codec2/vndk/util/C2ParamUtils.cpp b/media/codec2/vndk/util/C2ParamUtils.cpp
new file mode 100644
index 0000000..80573d8
--- /dev/null
+++ b/media/codec2/vndk/util/C2ParamUtils.cpp
@@ -0,0 +1,209 @@
+/*
+ * Copyright (C) 2016 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#define __C2_GENERATE_GLOBAL_VARS__ // to be able to implement the methods defined
+#include <C2Enum.h>
+#include <util/C2Debug-log.h>
+#include <util/C2ParamUtils.h>
+
+#include <utility>
+#include <vector>
+
+/** \file
+ * Utilities for parameter handling to be used by Codec2 implementations.
+ */
+
+/// \cond INTERNAL
+
+/* ---------------------------- UTILITIES FOR ENUMERATION REFLECTION ---------------------------- */
+
+static size_t countLeadingUnderscores(C2StringLiteral a) {
+    size_t i = 0;
+    while (a[i] == '_') {
+        ++i;
+    }
+    return i;
+}
+
+static size_t countMatching(C2StringLiteral a, const C2String &b) {
+    for (size_t i = 0; i < b.size(); ++i) {
+        if (!a[i] || a[i] != b[i]) {
+            return i;
+        }
+    }
+    return b.size();
+}
+
+// ABCDef => abc-def
+// ABCD2ef => abcd2-ef // 0
+// ABCD2Ef => ancd2-ef // -1
+// AbcDef => abc-def // -1
+// Abc2Def => abc-2def
+// Abc2def => abc-2-def
+// _Yo => _yo
+// _yo => _yo
+// C2_yo => c2-yo
+// C2__yo => c2-yo
+
+//static
+C2String _C2EnumUtils::camelCaseToDashed(C2String name) {
+    enum {
+        kNone = '.',
+        kLower = 'a',
+        kUpper = 'A',
+        kDigit = '1',
+        kDash = '-',
+        kUnderscore = '_',
+    } type = kNone;
+    size_t word_start = 0;
+    for (size_t ix = 0; ix < name.size(); ++ix) {
+        C2_LOG(VERBOSE) << name.substr(0, word_start) << "|"
+                << name.substr(word_start, ix - word_start) << "["
+                << name.substr(ix, 1) << "]" << name.substr(ix + 1)
+                << ": " << (char)type;
+        if (isupper(name[ix])) {
+            if (type == kLower) {
+                name.insert(ix++, 1, '-');
+                word_start = ix;
+            }
+            name[ix] = tolower(name[ix]);
+            type = kUpper;
+        } else if (islower(name[ix])) {
+            if (type == kDigit && ix > 0) {
+                name.insert(ix++, 1, '-');
+                word_start = ix;
+            } else if (type == kUpper && ix > word_start + 1) {
+                name.insert(ix++ - 1, 1, '-');
+                word_start = ix - 1;
+            }
+            type = kLower;
+        } else if (isdigit(name[ix])) {
+            if (type == kLower) {
+                name.insert(ix++, 1, '-');
+                word_start = ix;
+            }
+            type = kDigit;
+        } else if (name[ix] == '_') {
+            if (type == kDash) {
+                name.erase(ix--, 1);
+            } else if (type != kNone && type != kUnderscore) {
+                name[ix] = '-';
+                type = kDash;
+                word_start = ix + 1;
+            } else {
+                type = kUnderscore;
+                word_start = ix + 1;
+            }
+        } else {
+            name.resize(ix);
+        }
+    }
+    C2_LOG(VERBOSE) << "=> " << name;
+    return name;
+}
+
+//static
+std::vector<C2String> _C2EnumUtils::sanitizeEnumValueNames(
+        const std::vector<C2StringLiteral> names,
+        C2StringLiteral _prefix) {
+    std::vector<C2String> sanitizedNames;
+    C2String prefix;
+    size_t extraUnderscores = 0;
+    bool first = true;
+    if (_prefix) {
+        extraUnderscores = countLeadingUnderscores(_prefix);
+        prefix = _prefix + extraUnderscores;
+        first = false;
+        C2_LOG(VERBOSE) << "prefix:" << prefix << ", underscores:" << extraUnderscores;
+    }
+
+    // calculate prefix and minimum leading underscores
+    for (C2StringLiteral s : names) {
+        C2_LOG(VERBOSE) << s;
+        size_t underscores = countLeadingUnderscores(s);
+        if (first) {
+            extraUnderscores = underscores;
+            prefix = s + underscores;
+            first = false;
+        } else {
+            size_t matching = countMatching(
+                s + underscores,
+                prefix);
+            prefix.resize(matching);
+            extraUnderscores = std::min(underscores, extraUnderscores);
+        }
+        C2_LOG(VERBOSE) << "prefix:" << prefix << ", underscores:" << extraUnderscores;
+        if (prefix.size() == 0 && extraUnderscores == 0) {
+            break;
+        }
+    }
+
+    // we swallow the first underscore after upper case prefixes
+    bool upperCasePrefix = true;
+    for (size_t i = 0; i < prefix.size(); ++i) {
+        if (islower(prefix[i])) {
+            upperCasePrefix = false;
+            break;
+        }
+    }
+
+    for (C2StringLiteral s : names) {
+        size_t underscores = countLeadingUnderscores(s);
+        C2String sanitized = C2String(s, underscores - extraUnderscores);
+        sanitized.append(s + prefix.size() + underscores +
+                    (upperCasePrefix && s[prefix.size() + underscores] == '_'));
+        sanitizedNames.push_back(camelCaseToDashed(sanitized));
+    }
+
+    for (C2String s : sanitizedNames) {
+        C2_LOG(VERBOSE) << s;
+    }
+
+    return sanitizedNames;
+}
+
+//static
+std::vector<C2String> _C2EnumUtils::parseEnumValuesFromString(C2StringLiteral value) {
+    std::vector<C2String> foundNames;
+    size_t pos = 0, len = strlen(value);
+    do {
+        size_t endPos = strcspn(value + pos, " ,=") + pos;
+        if (endPos > pos) {
+            foundNames.emplace_back(value + pos, endPos - pos);
+        }
+        if (value[endPos] && value[endPos] != ',') {
+            endPos += strcspn(value + endPos, ",");
+        }
+        pos = strspn(value + endPos, " ,") + endPos;
+    } while (pos < len);
+    return foundNames;
+}
+
+/// safe(r) parsing from parameter blob
+//static
+C2Param *C2ParamUtils::ParseFirst(const uint8_t *blob, size_t size) {
+    // _mSize must fit into size, but really C2Param must also to be a valid param
+    if (size < sizeof(C2Param)) {
+        return nullptr;
+    }
+    // _mSize must match length
+    C2Param *param = (C2Param*)blob;
+    if (param->size() > size) {
+        return nullptr;
+    }
+    return param;
+}
+