add -l to list probes

src/CMakeLists.txt

@@ -12,6 +12,7 @@ add_executable(bpftrace
   mapkey.cpp
   printf.cpp
   types.cpp
+  list.cpp
 )
 
 target_link_libraries(bpftrace arch ast parser)

src/list.cpp

+#include <sys/types.h>
+#include <dirent.h>
+#include <fstream>
+#include <iomanip>
+#include <iostream>
+#include <sstream>
+#include <regex>
+#include <vector>
+#include <string>
+
+#include "list.h"
+#include "bpftrace.h"
+
+namespace bpftrace {
+
+const std::string kprobe_path = "/sys/kernel/debug/tracing/available_filter_functions";
+const std::string tp_path = "/sys/kernel/debug/tracing/events";
+
+bool search_probe(const std::string &probe, const std::string search)
+{
+  std::string s = search;
+  char remove[] = "*.?";
+  unsigned int i;
+
+  // TODO: glob searching instead of discarding wildcards
+  for (i = 0; i < strlen(remove); ++i)
+  {
+    s.erase(std::remove(s.begin(), s.end(), remove[i]), s.end());
+  }
+
+  if (probe.find(s) == std::string::npos)
+    return true;
+
+  return false;
+}
+
+void list_dir(const std::string path, std::vector<std::string> &files)
+{
+  // yes, I know about std::filesystem::directory_iterator, but no, it wasn't available
+  DIR *dp;
+  struct dirent *dep;
+  if ((dp = opendir(path.c_str())) == NULL)
+    return;
+
+  while ((dep = readdir(dp)) != NULL)
+    files.push_back(std::string(dep->d_name));
+}
+
+void list_probes(const std::string &search)
+{
+  unsigned int i, j;
+  std::string line, probe;
+
+  // software
+  // TODO: add here
+
+  // hardware
+  // TODO: add here
+
+  // tracepoints
+  std::vector<std::string> cats = std::vector<std::string>();
+  list_dir(tp_path, cats);
+  for (i = 0; i < cats.size(); i++)
+  {
+    if (cats[i] == "." || cats[i] == ".." || cats[i] == "enable" || cats[i] == "filter")
+      continue;
+    std::vector<std::string> events = std::vector<std::string>();
+    list_dir(tp_path + "/" + cats[i], events);
+    for (j = 0; j < events.size(); j++)
+    {
+      if (events[j] == "." || events[j] == ".." || events[j] == "enable" || events[j] == "filter")
+        continue;
+      probe = "tracepoint:" + cats[i] + ":" + events[j];
+      if (search_probe(probe, search))
+        continue;
+      std::cout << probe << std::endl;
+    }
+  }
+
+  // kprobes
+  std::cout << std::endl;
+  std::ifstream file(kprobe_path);
+  if (file.fail())
+  {
+    std::cerr << strerror(errno) << ": " << kprobe_path << std::endl;
+    return;
+  }
+
+  std::set<std::string> matches;
+  size_t loc;
+  while (std::getline(file, line))
+  {
+    loc = line.find_first_of(" ");
+    if (loc == std::string::npos)
+      probe = "kprobe:" + line;
+    else
+      probe = "kprobe:" + line.substr(0, loc);
+
+    if (!search.empty())
+    {
+      if (search_probe(probe, search))
+        continue;
+    }
+
+    std::cout << probe << std::endl;
+  }
+
+}
+
+void list_probes()
+{
+  const std::string search = "";
+  list_probes(search);
+}
+
+} // namespace bpftrace

src/list.h

+#include <sstream>
+
+namespace bpftrace {
+
+void list_probes(const std::string &search);
+void list_probes();
+
+} // namespace bpftrace

src/main.cpp

@@ -7,6 +7,7 @@
 #include "driver.h"
 #include "printer.h"
 #include "semantic_analyser.h"
+#include "list.h"
 
 using namespace bpftrace;
 
@@ -16,11 +17,14 @@ void usage()
   std::cerr << "    bpftrace [options] filename" << std::endl;
   std::cerr << "    bpftrace [options] -e 'program'" << std::endl << std::endl;
   std::cerr << "OPTIONS:" << std::endl;
+  std::cerr << "    -l [search]    list probes" << std::endl;
   std::cerr << "    -e 'program'   execute this program" << std::endl;
   std::cerr << "    -v    verbose messages" << std::endl;
   std::cerr << "    -d    debug info dry run" << std::endl << std::endl;
   std::cerr << "EXAMPLES:" << std::endl;
-  std::cerr << "bpftrace -e 'kprobe:sys_nanosleep { printf(\"PID %d sleeping...\\n\", pid); }'" << std::endl;
+  std::cerr << "bpftrace -l '*sleep*'" << std::endl;
+  std::cerr << "    list probes containing \"sleep\"" << std::endl;
+  std::cerr << "bpftrace -e 'kprobe:do_nanosleep { printf(\"PID %d sleeping...\\n\", pid); }'" << std::endl;
   std::cerr << "    trace processes calling sleep" << std::endl;
   std::cerr << "bpftrace -e 'tracepoint:raw_syscalls:sys_enter { @[comm] = count(); }'" << std::endl;
   std::cerr << "    count syscalls by process name" << std::endl;
@@ -30,10 +34,11 @@ int main(int argc, char *argv[])
 {
   int err;
   Driver driver;
+  bool listing = false;
 
-  std::string script;
+  std::string script, search;
   int c;
-  while ((c = getopt(argc, argv, "de:v")) != -1)
+  while ((c = getopt(argc, argv, "de:lv")) != -1)
   {
     switch (c)
     {
@@ -46,6 +51,9 @@ int main(int argc, char *argv[])
       case 'e':
         script = optarg;
         break;
+      case 'l':
+        listing = true;
+        break;
       default:
         usage();
         return 1;
@@ -59,6 +67,20 @@ int main(int argc, char *argv[])
     return 1;
   }
 
+  // Listing probes
+  if (listing)
+  {
+    if (optind == argc-1)
+      list_probes(argv[optind]);
+    else if (optind == argc)
+      list_probes();
+    else
+    {
+      usage();
+    }
+    return 0;
+  }
+
   if (script.empty())
   {
     // There should only be 1 non-option argument (the script file)