logcat: expand -n, -r and -b
- Add property expansion to the -n/--rotate-count,
-r/--rotate-kbytes and -b/--buffer parameters.
e.g. -r '${logcat.rotate-count:-6}' will expand the property
logcat.rotate-count, and if not present will default to 6
- Add gtest to confirm mid-stream expansion
- No longer support ",:;<whitespace>" for buffer tokenization,
settling on only supporting ",".
Bug: 28120456
Change-Id: I7ebb6146f72047631536c457952fa50d0abb98ab
diff --git a/logcat/logcat.cpp b/logcat/logcat.cpp
index fe5da19..52f49cc 100644
--- a/logcat/logcat.cpp
+++ b/logcat/logcat.cpp
@@ -27,6 +27,7 @@
#include <android-base/file.h>
#include <android-base/strings.h>
+#include <cutils/properties.h>
#include <cutils/sched_policy.h>
#include <cutils/sockets.h>
#include <log/event_tag_map.h>
@@ -280,10 +281,10 @@
fprintf(stderr, "options include:\n"
" -s Set default filter to silent. Equivalent to filterspec '*:S'\n"
" -f <file>, --file=<file> Log to file. Default is stdout\n"
- " -r <kbytes>, --rotate-kbytes=<kbytes>\n"
- " Rotate log every kbytes. Requires -f option\n"
- " -n <count>, --rotate-count=<count>\n"
- " Sets max number of rotated logs to <count>, default 4\n"
+ " -r <kbytes>, --rotate-kbytes=<kbytes> Rotate log every kbytes. Requires -f\n"
+ " option. Permits property expansion.\n"
+ " -n <count>, --rotate-count=<count> Sets max number of rotated logs to\n"
+ " <count>, default 4. Permits property expansion.\n"
" -v <format>, --format=<format>\n"
" Sets the log print format, where <format> is:\n"
" brief color epoch long monotonic printable process raw\n"
@@ -317,6 +318,7 @@
" 'system', 'radio', 'events', 'crash', 'default' or 'all'.\n"
" Multiple -b parameters or comma separated list of buffers are\n"
" allowed. Buffers interleaved. Default -b main,system,crash.\n"
+ " Permits property expansion.\n"
" -B, --binary Output the log in binary.\n"
" -S, --statistics Output statistics.\n"
" -p, --prune Print prune white and ~black list. Service is specified as\n"
@@ -334,7 +336,11 @@
" comes first. Improves efficiency of polling by providing\n"
" an about-to-wrap wakeup.\n");
- fprintf(stderr,"\nfilterspecs are a series of \n"
+ fprintf(stderr,"\nProperty expansion where available, may need to be single quoted to prevent\n"
+ "shell expansion:\n"
+ " ${key} - Expand string with property value associated with key\n"
+ " ${key:-default} - Expand, if property key value clear, use default\n"
+ "\nfilterspecs are a series of \n"
" <tag>[:priority]\n\n"
"where <tag> is a log component tag (or * for all) and priority is:\n"
" V Verbose (default for <tag>)\n"
@@ -391,7 +397,7 @@
}
/*String to unsigned int, returns -1 if it fails*/
-static bool getSizeTArg(char *ptr, size_t *val, size_t min = 0,
+static bool getSizeTArg(const char *ptr, size_t *val, size_t min = 0,
size_t max = SIZE_MAX)
{
if (!ptr) {
@@ -532,6 +538,49 @@
return retval;
}
+// Expand multiple flat property references ${<tag>:-default} or ${tag}.
+//
+// ToDo: Do we permit nesting?
+// ${persist.logcat.something:-${ro.logcat.something:-maybesomething}}
+// For now this will result in a syntax error for caller and is acceptable.
+//
+std::string expand(const char *str)
+{
+ std::string retval(str);
+
+ // Caller has no use for ${, } or :- as literals so no use for escape
+ // character. Result expectations are a number or a string, with validity
+ // checking for both in caller. Recursive expansion or other syntax errors
+ // will result in content caller can not obviously tolerate, error must
+ // report substring if applicable, expanded and original content (if
+ // different) so that it will be clear to user what they did wrong.
+ for (size_t pos; (pos = retval.find("${")) != std::string::npos; ) {
+ size_t epos = retval.find("}", pos + 2);
+ if (epos == std::string::npos) {
+ break; // Caller will error out, showing this unexpanded.
+ }
+ size_t def = retval.find(":-", pos + 2);
+ if (def >= epos) {
+ def = std::string::npos;
+ }
+ std::string default_value("");
+ std::string key;
+ if (def == std::string::npos) {
+ key = retval.substr(pos + 2, epos - (pos + 2));
+ } else {
+ key = retval.substr(pos + 2, def - (pos + 2));
+ default_value = retval.substr(def + 2, epos - (def + 2));
+ }
+ char value[PROPERTY_VALUE_MAX];
+ property_get(key.c_str(), value, default_value.c_str());
+ // Caller will error out, syntactically empty content at this point
+ // will not be tolerated as expected.
+ retval.replace(pos, epos - pos + 1, value);
+ }
+
+ return retval;
+}
+
} /* namespace android */
@@ -763,23 +812,35 @@
case 'b': {
unsigned idMask = 0;
- while ((optarg = strtok(optarg, ",:; \t\n\r\f")) != NULL) {
- if (strcmp(optarg, "default") == 0) {
+ std::string expanded = expand(optarg);
+ std::istringstream copy(expanded);
+ std::string token;
+ // wish for strtok and ",:; \t\n\r\f" for hidden flexibility
+ while (std::getline(copy, token, ',')) { // settle for ","
+ if (token.compare("default") == 0) {
idMask |= (1 << LOG_ID_MAIN) |
(1 << LOG_ID_SYSTEM) |
(1 << LOG_ID_CRASH);
- } else if (strcmp(optarg, "all") == 0) {
+ } else if (token.compare("all") == 0) {
idMask = (unsigned)-1;
} else {
- log_id_t log_id = android_name_to_log_id(optarg);
+ log_id_t log_id = android_name_to_log_id(token.c_str());
const char *name = android_log_id_to_name(log_id);
- if (strcmp(name, optarg) != 0) {
- logcat_panic(true, "unknown buffer %s\n", optarg);
+ if (token.compare(name) != 0) {
+ bool strDifferent = expanded.compare(token);
+ if (expanded.compare(optarg)) {
+ expanded += " expanded from ";
+ expanded += optarg;
+ }
+ if (strDifferent) {
+ expanded = token + " within " + expanded;
+ }
+ logcat_panic(true, "unknown buffer -b %s\n",
+ expanded.c_str());
}
idMask |= (1 << log_id);
}
- optarg = NULL;
}
for (int i = LOG_ID_MIN; i < LOG_ID_MAX; ++i) {
@@ -834,22 +895,36 @@
g_outputFileName = optarg;
break;
- case 'r':
- if (!getSizeTArg(optarg, &g_logRotateSizeKBytes, 1)) {
- logcat_panic(true, "Invalid parameter %s to -r\n", optarg);
+ case 'r': {
+ std::string expanded = expand(optarg);
+ if (!getSizeTArg(expanded.c_str(), &g_logRotateSizeKBytes, 1)) {
+ if (expanded.compare(optarg)) {
+ expanded += " expanded from ";
+ expanded += optarg;
+ }
+ logcat_panic(true, "Invalid parameter -r %s\n",
+ expanded.c_str());
}
+ }
break;
- case 'n':
- if (!getSizeTArg(optarg, &g_maxRotatedLogs, 1)) {
- logcat_panic(true, "Invalid parameter %s to -n\n", optarg);
+ case 'n': {
+ std::string expanded = expand(optarg);
+ if (!getSizeTArg(expanded.c_str(), &g_maxRotatedLogs, 1)) {
+ if (expanded.compare(optarg)) {
+ expanded += " expanded from ";
+ expanded += optarg;
+ }
+ logcat_panic(true, "Invalid parameter -n %s\n",
+ expanded.c_str());
}
+ }
break;
case 'v':
err = setLogFormat (optarg);
if (err < 0) {
- logcat_panic(true, "Invalid parameter %s to -v\n", optarg);
+ logcat_panic(true, "Invalid parameter -v %s\n", optarg);
}
hasSetLogFormat |= err;
break;