diff options
Diffstat (limited to 'hash.cxx')
| -rw-r--r-- | hash.cxx | 154 |
1 files changed, 99 insertions, 55 deletions
@@ -65,22 +65,83 @@ hash::result(string& r) } -void -find_hash (systemtap_session& s, const string& script) +static void +get_base_hash (systemtap_session& s, hash& h) { - hash h; - int nlevels = 1; struct stat st; - // We use a N level subdir for the cache path. Let N be adjustable. - const char *s_n; - if ((s_n = getenv("SYSTEMTAP_NLEVELS"))) + // Hash kernel release and arch. + h.add(s.kernel_release); + h.add(s.kernel_build_tree); + h.add(s.architecture); + + // Hash runtime path (that gets added in as "-R path"). + h.add(s.runtime_path); + + // Hash compiler path, size, and mtime. We're just going to assume + // we'll be using gcc. XXX: getting kbuild to spit out out would be + // better. + string gcc_path = find_executable ("gcc"); + if (stat(gcc_path.c_str(), &st) == 0) + { + h.add(gcc_path); + h.add(st.st_size); + h.add(st.st_mtime); + } + + // Hash the systemtap size and mtime. We could use VERSION/DATE, + // but when developing systemtap that doesn't work well (since you + // can compile systemtap multiple times in 1 day). Since we don't + // know exactly where we're getting run from, we'll use + // /proc/self/exe. + if (stat("/proc/self/exe", &st) == 0) + { + h.add(st.st_size); + h.add(st.st_mtime); + } +} + + +static bool +create_hashdir (systemtap_session& s, const string& result, string& hashdir) +{ + int nlevels = 1; + + // Use a N level subdir for the cache path to reduce the impact on + // filesystems which are slow for large directories. Let N be adjustable. + const char *s_n = getenv("SYSTEMTAP_NLEVELS"); + if (s_n) { nlevels = atoi(s_n); if (nlevels < 1) nlevels = 1; if (nlevels > 8) nlevels = 8; } + hashdir = s.cache_path; + + for (int i = 0; i < nlevels; i++) + { + hashdir += string("/") + result[i*2] + result[i*2 + 1]; + if (create_dir(hashdir.c_str()) != 0) + { + if (! s.suppress_warnings) + cerr << "Warning: failed to create cache directory (\"" + << hashdir + "\"): " << strerror(errno) + << ", disabling cache support." << endl; + s.use_cache = false; + return false; + } + } + return true; +} + + +static void +find_script_hash (systemtap_session& s, const string& script, const hash &base) +{ + hash h(base); + struct stat st; + // Hash getuid. This really shouldn't be necessary (since who you // are doesn't change the generated output), but the hash gets used // as the module name. If two different users try to run the same @@ -88,11 +149,6 @@ find_hash (systemtap_session& s, const string& script) // module name. h.add(getuid()); - // Hash kernel release and arch. - h.add(s.kernel_release); - h.add(s.kernel_build_tree); - h.add(s.architecture); - // Hash user-specified arguments (that change the generated module). h.add(s.bulk_mode); // '-b' h.add(s.merge); // '-M' @@ -123,53 +179,14 @@ find_hash (systemtap_session& s, const string& script) h.add(*it); // XXX: a build-id of each module might be even better - // Hash runtime path (that gets added in as "-R path"). - h.add(s.runtime_path); - - // Hash compiler path, size, and mtime. We're just going to assume - // we'll be using gcc. XXX: getting kbuild to spit out out would be - // better. - string gcc_path = find_executable ("gcc"); - if (stat(gcc_path.c_str(), &st) == 0) - { - h.add(gcc_path); - h.add(st.st_size); - h.add(st.st_mtime); - } - - // Hash the systemtap size and mtime. We could use VERSION/DATE, - // but when developing systemtap that doesn't work well (since you - // can compile systemtap multiple times in 1 day). Since we don't - // know exactly where we're getting run from, we'll use - // /proc/self/exe. - if (stat("/proc/self/exe", &st) == 0) - { - h.add(st.st_size); - h.add(st.st_mtime); - } - // Add in pass 2 script output. h.add(script); - // Use a N level subdir for the cache path to reduce the impact on - // filesystems which are slow for large directories. - string hashdir = s.cache_path; - string result; + // Get the directory path to store our cached script + string result, hashdir; h.result(result); - - for (int i = 0; i < nlevels; i++) - { - hashdir += string("/") + result[i*2] + result[i*2 + 1]; - if (create_dir(hashdir.c_str()) != 0) - { - if (! s.suppress_warnings) - cerr << "Warning: failed to create cache directory (\"" - << hashdir + "\"): " << strerror(errno) - << ", disabling cache support." << endl; - s.use_cache = false; - return; - } - } + if (!create_hashdir(s, result, hashdir)) + return; // Update module name to be 'stap_{hash start}'. '{hash start}' // must not be too long. This shouldn't happen, since the maximum @@ -192,4 +209,31 @@ find_hash (systemtap_session& s, const string& script) s.translated_source = string(s.tmpdir) + "/" + s.module_name + ".c"; } + +static void +find_stapconf_hash (systemtap_session& s, const hash& base) +{ + hash h(base); + + // The basic hash should be good enough for STAPCONF variables + + // Get the directory path to store our cached stapconf parameters + string result, hashdir; + h.result(result); + if (!create_hashdir(s, result, hashdir)) + return; + + s.stapconf_path = hashdir + "/stapconf_" + result; +} + + +void +find_hash (systemtap_session& s, const string& script) +{ + hash base; + get_base_hash(s, base); + find_stapconf_hash(s, base); + find_script_hash(s, script, base); +} + /* vim: set sw=2 ts=8 cino=>4,n-2,{2,^-2,t0,(0,u0,w1,M1 : */ |