1 /* 2 * Copyright 2014 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 #include <errno.h> 18 #include <stdlib.h> 19 #include <ctype.h> 20 21 #define LOG_TAG "ADebug" 22 #include <cutils/atomic.h> 23 #include <utils/Log.h> 24 #include <utils/misc.h> 25 26 #include <cutils/properties.h> 27 28 #include <ADebug.h> 29 #include <AStringUtils.h> 30 #include <AUtils.h> 31 32 #define UNUSED(x) ((void)(x)) 33 34 namespace android { 35 36 //static GetLevelFromSettingsString(const char * name,const char * value,long def)37 long ADebug::GetLevelFromSettingsString( 38 const char *name, const char *value, long def) { 39 // split on , 40 const char *next = value, *current; 41 while (next != NULL) { 42 current = next; 43 next = strchr(current, ','); 44 if (next != NULL) { 45 ++next; // pass , 46 } 47 48 while (isspace(*current)) { 49 ++current; 50 } 51 // check for : 52 char *colon = strchr(current, ':'); 53 54 // get level 55 char *end; 56 errno = 0; // strtol does not clear errno, but it can be set for any return value 57 long level = strtol(current, &end, 10); 58 while (isspace(*end)) { 59 ++end; 60 } 61 if (errno != 0 || end == current || (end != colon && *end != '\0' && end != next)) { 62 // invalid level - skip 63 continue; 64 } 65 if (colon != NULL) { 66 // check if pattern matches 67 do { // skip colon and spaces 68 ++colon; 69 } while (isspace(*colon)); 70 size_t globLen = (next == NULL ? strlen(colon) : (next - 1 - colon)); 71 while (globLen > 0 && isspace(colon[globLen - 1])) { 72 --globLen; // trim glob 73 } 74 75 if (!AStringUtils::MatchesGlob( 76 colon, globLen, name, strlen(name), true /* ignoreCase */)) { 77 continue; 78 } 79 } 80 81 // update value 82 def = level; 83 } 84 return def; 85 } 86 87 //static GetLevelFromProperty(const char * name,const char * propertyName,long def)88 long ADebug::GetLevelFromProperty( 89 const char *name, const char *propertyName, long def) { 90 char value[PROPERTY_VALUE_MAX]; 91 if (property_get(propertyName, value, NULL)) { 92 def = GetLevelFromSettingsString(name, value, def); 93 } 94 return def; 95 } 96 97 //static GetDebugLevelFromProperty(const char * name,const char * propertyName,ADebug::Level def)98 ADebug::Level ADebug::GetDebugLevelFromProperty( 99 const char *name, const char *propertyName, ADebug::Level def) { 100 long level = GetLevelFromProperty(name, propertyName, (long)def); 101 return (Level)min(max(level, (long)kDebugNone), (long)kDebugMax); 102 } 103 104 //static GetDebugName(const char * name)105 char *ADebug::GetDebugName(const char *name) { 106 char *debugName = strdup(name); 107 const char *terms[] = { "omx", "video", "audio" }; 108 for (size_t i = 0; i < NELEM(terms) && debugName != NULL; i++) { 109 const char *term = terms[i]; 110 const size_t len = strlen(term); 111 char *match = strcasestr(debugName, term); 112 if (match != NULL && (match == debugName || match[-1] == '.' 113 || match[len] == '.' || match[len] == '\0')) { 114 char *src = match + len; 115 if (match == debugName || match[-1] == '.') { 116 src += (*src == '.'); // remove trailing or double . 117 } 118 memmove(match, src, debugName + strlen(debugName) - src + 1); 119 } 120 } 121 122 return debugName; 123 } 124 125 //static getExperimentFlag(bool allow,const char * name,uint64_t modulo,uint64_t limit,uint64_t plus,uint64_t timeDivisor)126 bool ADebug::getExperimentFlag( 127 bool allow, const char *name, uint64_t modulo, 128 uint64_t limit, uint64_t plus, uint64_t timeDivisor) { 129 // see if this experiment should be disabled/enabled based on properties. 130 // default to 2 to allow 0/1 specification 131 const int undefined = 2; 132 long level = GetLevelFromProperty(name, "debug.stagefright.experiments", undefined); 133 if (level != undefined) { 134 ALOGI("experiment '%s': %s from property", name, level ? "ENABLED" : "disabled"); 135 return allow && (level != 0); 136 } 137 138 #ifndef ENABLE_STAGEFRIGHT_AUTO_EXPERIMENTS 139 UNUSED(modulo); 140 UNUSED(limit); 141 UNUSED(plus); 142 UNUSED(timeDivisor); 143 return false; 144 #else 145 // Disable automatic experiments in "non-experimental" builds (that is, _all_ builds 146 // as there is no "experimental" build). 147 // TODO: change build type to enable automatic experiments in the future for some builds 148 char value[PROPERTY_VALUE_MAX]; 149 if (property_get("ro.build.type", value, NULL)) { 150 if (strcmp(value, "experimental")) { 151 return false; 152 } 153 } 154 155 static volatile int32_t haveSerial = 0; 156 static uint64_t serialNum; 157 if (!android_atomic_acquire_load(&haveSerial)) { 158 // calculate initial counter value based on serial number 159 static char serial[PROPERTY_VALUE_MAX]; 160 property_get("ro.serialno", serial, "0"); 161 uint64_t num = 0; // it is okay for this number to overflow 162 for (size_t i = 0; i < NELEM(serial) && serial[i] != '\0'; ++i) { 163 const char &c = serial[i]; 164 // try to use most letters of serialno 165 if (isdigit(c)) { 166 num = num * 10 + (c - '0'); 167 } else if (islower(c)) { 168 num = num * 26 + (c - 'a'); 169 } else if (isupper(c)) { 170 num = num * 26 + (c - 'A'); 171 } else { 172 num = num * 256 + c; 173 } 174 } 175 serialNum = num; 176 android_atomic_release_store(1, &haveSerial); 177 } 178 ALOGD("serial: %llu, time: %lld", (long long unsigned)serialNum, (long long)time(NULL)); 179 // MINOR: use modulo for counter and time, so that their sum does not 180 // roll over, and mess up the correlation between related experiments. 181 // e.g. keep (a mod 2N) = 0 impl (a mod N) = 0 182 time_t counter = (time(NULL) / timeDivisor) % modulo + plus + serialNum % modulo; 183 bool enable = allow && (counter % modulo < limit); 184 ALOGI("experiment '%s': %s", name, enable ? "ENABLED" : "disabled"); 185 return enable; 186 #endif 187 } 188 189 } // namespace android 190 191