buildrun.cxx

   1 // build/run probes
   2 // Copyright (C) 2005-2014 Red Hat Inc.
   3 //
   4 // This file is part of systemtap, and is free software.  You can
   5 // redistribute it and/or modify it under the terms of the GNU General
   6 // Public License (GPL); either version 2, or (at your option) any
   7 // later version.
   8
   9 #include "config.h"
  10 #include "buildrun.h"
  11 #include "session.h"
  12 #include "util.h"
  13 #include "hash.h"
  14 #include "translate.h"
  15
  16 #include <cstdlib>
  17 #include <fstream>
  18 #include <sstream>
  19
  20 extern "C" {
  21 #include <signal.h>
  22 #include <sys/wait.h>
  23 #include <pwd.h>
  24 #include <grp.h>
  25 #include <sys/types.h>
  26 #include <sys/stat.h>
  27 #include <unistd.h>
  28 #include <string.h>
  29 #include <errno.h>
  30 #include <sys/resource.h>
  31 }
  32
  33 // A bit of obfuscation for Gentoo's sake.
  34 // We *need* -Werror for stapconf to work correctly.
  35 // https://bugs.gentoo.org/show_bug.cgi?id=522908
  36 #define WERROR ("-W" "error")
  37
  38 using namespace std;
  39
  40 /* Adjust and run make_cmd to build a kernel module. */
  41 static int
  42 run_make_cmd(systemtap_session& s, vector<string>& make_cmd,
  43              bool null_out=false, bool null_err=false)
  44 {
  45   assert_no_interrupts();
  46
  47   // PR14168: we used to unsetenv values here; instead do it via
  48   // env(1) in make_any_make_cmd().
  49
  50   // Disable ccache to avoid saving files that will never be reused.
  51   // (ccache is useless to us, because our compiler commands always
  52   // include the randomized tmpdir path.)
  53   // It's not critical if this fails, so the return is ignored.
  54   (void) setenv("CCACHE_DISABLE", "1", 0);
  55
  56   if (s.verbose > 2)
  57     make_cmd.push_back("V=1");
  58   else if (s.verbose > 1)
  59     make_cmd.push_back("--no-print-directory");
  60   else
  61     {
  62       make_cmd.push_back("-s");
  63       make_cmd.push_back("--no-print-directory");
  64     }
  65
  66   // Exploit SMP parallelism, if available.
  67   long smp = sysconf(_SC_NPROCESSORS_ONLN);
  68   if (smp <= 0) smp = 1;
  69   // PR16276: but only if we're not running severely nproc-rlimited
  70   struct rlimit rlim;
  71   int rlimit_rc = getrlimit(RLIMIT_NPROC, &rlim);
  72   const unsigned int severely_limited = smp*30; // WAG at number of gcc+make etc. nested processes
  73   bool nproc_limited = (rlimit_rc == 0 && (rlim.rlim_max <= severely_limited ||
  74                                            rlim.rlim_cur <= severely_limited));
  75   if (smp >= 1 && !nproc_limited)
  76     make_cmd.push_back("-j" + lex_cast(smp+1));
  77
  78   if (strverscmp (s.kernel_base_release.c_str(), "2.6.29") < 0)
  79     {
  80       // Older kernels, before linux commit #fd54f502841c1, include
  81       // gratuitous "echo"s in their Makefile.  We need to suppress
  82       // that with this bluntness.
  83       null_out = true;
  84     }
  85
  86   int rc = stap_system (s.verbose, "kbuild", make_cmd, null_out, null_err);
  87   if (rc != 0)
  88     s.set_try_server ();
  89   return rc;
  90 }
  91
  92 static vector<string>
  93 make_any_make_cmd(systemtap_session& s, const string& dir, const string& target)
  94 {
  95   vector<string> make_cmd;
  96
  97   // PR14168: sanitize environment variables for kbuild invocation
  98   make_cmd.push_back("env");
  99   make_cmd.push_back("-uARCH");
 100   make_cmd.push_back("-uKBUILD_EXTMOD");
 101   make_cmd.push_back("-uCROSS_COMPILE");
 102   make_cmd.push_back("-uKBUILD_IMAGE");
 103   make_cmd.push_back("-uKCONFIG_CONFIG");
 104   make_cmd.push_back("-uINSTALL_PATH");
 105   string newpath = string("PATH=/usr/bin:/bin:") + (getenv("PATH") ?: "");
 106   make_cmd.push_back(newpath.c_str());
 107
 108   make_cmd.push_back("make");
 109   make_cmd.push_back("-C");
 110   make_cmd.push_back(s.kernel_build_tree);
 111   make_cmd.push_back("M=" + dir); // need make-quoting?
 112   make_cmd.push_back(target);
 113
 114   // Add architecture, except for old powerpc (RHBZ669082)
 115   if (s.architecture != "powerpc" ||
 116       (strverscmp (s.kernel_base_release.c_str(), "2.6.15") >= 0))
 117     make_cmd.push_back("ARCH=" + s.architecture); // need make-quoting?
 118
 119   // PR13847: suppress debuginfo creation by default
 120   make_cmd.insert(make_cmd.end(), "CONFIG_DEBUG_INFO=");
 121
 122   // Add any custom kbuild flags
 123   make_cmd.insert(make_cmd.end(), s.kbuildflags.begin(), s.kbuildflags.end());
 124
 125   return make_cmd;
 126 }
 127
 128 static vector<string>
 129 make_make_cmd(systemtap_session& s, const string& dir)
 130 {
 131   return make_any_make_cmd(s, dir, "modules");
 132 }
 133
 134 static vector<string>
 135 make_make_objs_cmd(systemtap_session& s, const string& dir)
 136 {
 137   // Kbuild uses these rules to build external modules:
 138   //
 139   //   module-dirs := $(addprefix _module_,$(KBUILD_EXTMOD))
 140   //   modules: $(module-dirs)
 141   //       @$(kecho) '  Building modules, stage 2.';
 142   //       $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
 143   //
 144   // So if we're only interested in the stage 1 objects, we can
 145   // cheat and make only the $(module-dirs) part.
 146   return make_any_make_cmd(s, dir, "_module_" + dir);
 147 }
 148
 149 static void
 150 output_autoconf(systemtap_session& s, ofstream& o, const char *autoconf_c,
 151                 const char *deftrue, const char *deffalse)
 152 {
 153   o << "\t";
 154   if (s.verbose < 4)
 155     o << "@";
 156   o << "if $(CHECK_BUILD) $(SYSTEMTAP_RUNTIME)/linux/" << autoconf_c;
 157   if (s.verbose < 5)
 158     o << " > /dev/null 2>&1";
 159   o << "; then ";
 160   if (deftrue)
 161     o << "echo \"#define " << deftrue << " 1\"";
 162   if (deffalse)
 163     o << "; else echo \"#define " << deffalse << " 1\"";
 164   o << "; fi >> $@" << endl;
 165 }
 166
 167
 168 void output_exportconf(systemtap_session& s, ofstream& o, const char *symbol,
 169                      const char *deftrue)
 170 {
 171   o << "\t";
 172   if (s.verbose < 4)
 173     o << "@";
 174   if (s.kernel_exports.find(symbol) != s.kernel_exports.end())
 175     o << "echo \"#define " << deftrue << " 1\"";
 176   o << ">> $@" << endl;
 177 }
 178
 179
 180 void output_dual_exportconf(systemtap_session& s, ofstream& o,
 181                             const char *symbol1, const char *symbol2,
 182                             const char *deftrue)
 183 {
 184   o << "\t";
 185   if (s.verbose < 4)
 186     o << "@";
 187   if (s.kernel_exports.find(symbol1) != s.kernel_exports.end()
 188       && s.kernel_exports.find(symbol2) != s.kernel_exports.end())
 189     o << "echo \"#define " << deftrue << " 1\"";
 190   o << ">> $@" << endl;
 191 }
 192
 193
 194 void output_either_exportconf(systemtap_session& s, ofstream& o,
 195                               const char *symbol1, const char *symbol2,
 196                               const char *deftrue)
 197 {
 198   o << "\t";
 199   if (s.verbose < 4)
 200     o << "@";
 201   if (s.kernel_exports.find(symbol1) != s.kernel_exports.end()
 202       || s.kernel_exports.find(symbol2) != s.kernel_exports.end())
 203     o << "echo \"#define " << deftrue << " 1\"";
 204   o << ">> $@" << endl;
 205 }
 206
 207
 208 static int
 209 compile_dyninst (systemtap_session& s)
 210 {
 211   const string module = s.tmpdir + "/" + s.module_filename();
 212
 213   vector<string> cmd;
 214   cmd.push_back("gcc");
 215   cmd.push_back("--std=gnu99");
 216   cmd.push_back("-Wall");
 217   cmd.push_back(WERROR);
 218   cmd.push_back("-Wno-unused");
 219   cmd.push_back("-Wno-strict-aliasing");
 220
 221   // BZ855981/948279.  Since dyninst/runtime.h includes __sync_* calls,
 222   // the compiler may generate different code for it depending on -march.
 223   // For example, if the default is i386, we may get references to auxiliary
 224   // functions like __sync_add_and_fetch_4, which appear to be defined
 225   // nowhere.  We hack around this problem thusly:
 226   if (s.architecture == "i386")
 227     cmd.push_back("-march=i586");
 228
 229   cmd.push_back("-fvisibility=hidden");
 230   cmd.push_back("-O2");
 231   cmd.push_back("-I" + s.runtime_path);
 232   cmd.push_back("-D__DYNINST__");
 233   for (size_t i = 0; i < s.c_macros.size(); ++i)
 234     cmd.push_back("-D" + s.c_macros[i]);
 235   cmd.push_back(s.translated_source);
 236   cmd.push_back("-pthread");
 237   cmd.push_back("-lrt");
 238   cmd.push_back("-fPIC");
 239   cmd.push_back("-shared");
 240   cmd.push_back("-o");
 241   cmd.push_back(module);
 242   if (s.verbose > 3)
 243     {
 244       cmd.push_back("-ftime-report");
 245       cmd.push_back("-Q");
 246     }
 247
 248   int rc = stap_system (s.verbose, cmd);
 249   if (rc)
 250     s.set_try_server ();
 251   return rc;
 252 }
 253
 254
 255 int
 256 compile_pass (systemtap_session& s)
 257 {
 258   if (s.runtime_usermode_p())
 259     return compile_dyninst (s);
 260
 261   int rc = uprobes_pass (s);
 262   if (rc)
 263     {
 264       s.set_try_server ();
 265       return rc;
 266     }
 267
 268   // fill in a quick Makefile
 269   string makefile_nm = s.tmpdir + "/Makefile";
 270   ofstream o (makefile_nm.c_str());
 271
 272   // Create makefile
 273
 274   // Clever hacks copied from vmware modules
 275   string superverbose;
 276   if (s.verbose > 3)
 277     superverbose = "set -x;";
 278
 279   string redirecterrors = "> /dev/null 2>&1";
 280   if (s.verbose > 6)
 281     redirecterrors = "";
 282
 283   // Support O= (or KBUILD_OUTPUT) option
 284   o << "_KBUILD_CFLAGS := $(call flags,KBUILD_CFLAGS)" << endl;
 285
 286   o << "stap_check_gcc = $(shell " << superverbose
 287     << " if $(CC) $(1) -S -o /dev/null -xc /dev/null > /dev/null 2>&1; then "
 288     << "echo \"$(1)\"; else echo \"$(2)\"; fi)" << endl;
 289   o << "CHECK_BUILD := $(CC) $(NOSTDINC_FLAGS) $(KBUILD_CPPFLAGS) $(CPPFLAGS) "
 290     << "$(LINUXINCLUDE) $(_KBUILD_CFLAGS) $(CFLAGS_KERNEL) $(EXTRA_CFLAGS) "
 291     << "$(CFLAGS) -DKBUILD_BASENAME=\\\"" << s.module_name << "\\\" "
 292     << WERROR << " -S -o /dev/null -xc " << endl;
 293   o << "stap_check_build = $(shell " << superverbose << " if $(CHECK_BUILD) $(1) "
 294     << redirecterrors << " ; then echo \"$(2)\"; else echo \"$(3)\"; fi)" << endl;
 295
 296   o << "SYSTEMTAP_RUNTIME = \"" << s.runtime_path << "\"" << endl;
 297
 298   // "autoconf" options go here
 299
 300   // RHBZ 543529: early rhel6 kernels' module-signing kbuild logic breaks out-of-tree modules
 301   o << "CONFIG_MODULE_SIG := n" << endl;
 302
 303   string module_cflags = "EXTRA_CFLAGS";
 304   o << module_cflags << " :=" << endl;
 305
 306   // XXX: This gruesome hack is needed on some kernels built with separate O=directory,
 307   // where files like 2.6.27 x86's asm/mach-*/mach_mpspec.h are not found on the cpp path.
 308   // This could be a bug in arch/x86/Makefile that names
 309   //      mflags-y += -Iinclude/asm-x86/mach-default
 310   // but that path does not exist in an O= build tree.
 311   o << module_cflags << " += -Iinclude2/asm/mach-default" << endl;
 312   o << module_cflags << " += -I" + s.kernel_build_tree << endl;
 313   if (s.kernel_source_tree != "")
 314     o << module_cflags << " += -I" + s.kernel_source_tree << endl;
 315   for (unsigned i = 0; i < s.kernel_extra_cflags.size(); i++)
 316     o << module_cflags << " += " + s.kernel_extra_cflags[i] << endl;
 317
 318   // NB: don't try
 319   // o << module_cflags << " += -Iusr/include" << endl;
 320   // since such headers are cleansed of _KERNEL_ pieces that we need
 321
 322   o << "STAPCONF_HEADER := " << s.tmpdir << "/" << s.stapconf_name << endl;
 323   o << "$(STAPCONF_HEADER):" << endl;
 324   o << "\t@> $@" << endl;
 325   output_autoconf(s, o, "autoconf-hrtimer-rel.c", "STAPCONF_HRTIMER_REL", NULL);
 326   output_exportconf(s, o, "hrtimer_get_res", "STAPCONF_HRTIMER_GET_RES");
 327   output_autoconf(s, o, "autoconf-generated-compile.c", "STAPCONF_GENERATED_COMPILE", NULL);
 328   output_autoconf(s, o, "autoconf-hrtimer-getset-expires.c", "STAPCONF_HRTIMER_GETSET_EXPIRES", NULL);
 329   output_autoconf(s, o, "autoconf-inode-private.c", "STAPCONF_INODE_PRIVATE", NULL);
 330   output_autoconf(s, o, "autoconf-constant-tsc.c", "STAPCONF_CONSTANT_TSC", NULL);
 331   output_autoconf(s, o, "autoconf-ktime-get-real.c", "STAPCONF_KTIME_GET_REAL", NULL);
 332   output_autoconf(s, o, "autoconf-x86-uniregs.c", "STAPCONF_X86_UNIREGS", NULL);
 333   output_autoconf(s, o, "autoconf-nameidata.c", "STAPCONF_NAMEIDATA_CLEANUP", NULL);
 334   output_dual_exportconf(s, o, "unregister_kprobes", "unregister_kretprobes", "STAPCONF_UNREGISTER_KPROBES");
 335   output_autoconf(s, o, "autoconf-kprobe-symbol-name.c", "STAPCONF_KPROBE_SYMBOL_NAME", NULL);
 336   output_autoconf(s, o, "autoconf-real-parent.c", "STAPCONF_REAL_PARENT", NULL);
 337   output_autoconf(s, o, "autoconf-uaccess.c", "STAPCONF_LINUX_UACCESS_H", NULL);
 338   output_autoconf(s, o, "autoconf-oneachcpu-retry.c", "STAPCONF_ONEACHCPU_RETRY", NULL);
 339   output_autoconf(s, o, "autoconf-dpath-path.c", "STAPCONF_DPATH_PATH", NULL);
 340   output_exportconf(s, o, "synchronize_kernel", "STAPCONF_SYNCHRONIZE_KERNEL");
 341   output_exportconf(s, o, "synchronize_rcu", "STAPCONF_SYNCHRONIZE_RCU");
 342   output_exportconf(s, o, "synchronize_sched", "STAPCONF_SYNCHRONIZE_SCHED");
 343   output_autoconf(s, o, "autoconf-task-uid.c", "STAPCONF_TASK_UID", NULL);
 344   output_autoconf(s, o, "autoconf-from_kuid_munged.c", "STAPCONF_FROM_KUID_MUNGED", NULL);
 345   output_exportconf(s, o, "get_mm_exe_file", "STAPCONF_GET_MM_EXE_FILE");
 346   output_dual_exportconf(s, o, "alloc_vm_area", "free_vm_area", "STAPCONF_VM_AREA");
 347   output_autoconf(s, o, "autoconf-procfs-owner.c", "STAPCONF_PROCFS_OWNER", NULL);
 348   output_autoconf(s, o, "autoconf-alloc-percpu-align.c", "STAPCONF_ALLOC_PERCPU_ALIGN", NULL);
 349   output_autoconf(s, o, "autoconf-x86-fs.c", "STAPCONF_X86_FS", NULL);
 350   output_autoconf(s, o, "autoconf-x86-xfs.c", "STAPCONF_X86_XFS", NULL);
 351   output_autoconf(s, o, "autoconf-x86-gs.c", "STAPCONF_X86_GS", NULL);
 352   output_autoconf(s, o, "autoconf-grsecurity.c", "STAPCONF_GRSECURITY", NULL);
 353   output_autoconf(s, o, "autoconf-trace-printk.c", "STAPCONF_TRACE_PRINTK", NULL);
 354   output_autoconf(s, o, "autoconf-regset.c", "STAPCONF_REGSET", NULL);
 355   output_autoconf(s, o, "autoconf-utrace-regset.c", "STAPCONF_UTRACE_REGSET", NULL);
 356   output_autoconf(s, o, "autoconf-uprobe-get-pc.c", "STAPCONF_UPROBE_GET_PC", NULL);
 357   output_autoconf(s, o, "autoconf-hlist-4args.c", "STAPCONF_HLIST_4ARGS", NULL);
 358   output_exportconf(s, o, "tsc_khz", "STAPCONF_TSC_KHZ");
 359   output_exportconf(s, o, "cpu_khz", "STAPCONF_CPU_KHZ");
 360   output_exportconf(s, o, "__module_text_address", "STAPCONF_MODULE_TEXT_ADDRESS");
 361   output_exportconf(s, o, "add_timer_on", "STAPCONF_ADD_TIMER_ON");
 362
 363   output_dual_exportconf(s, o, "probe_kernel_read", "probe_kernel_write", "STAPCONF_PROBE_KERNEL");
 364   output_autoconf(s, o, "autoconf-hw_breakpoint_context.c",
 365                   "STAPCONF_HW_BREAKPOINT_CONTEXT", NULL);
 366   output_autoconf(s, o, "autoconf-save-stack-trace.c",
 367                   "STAPCONF_KERNEL_STACKTRACE", NULL);
 368   output_autoconf(s, o, "autoconf-save-stack-trace-no-bp.c",
 369                   "STAPCONF_KERNEL_STACKTRACE_NO_BP", NULL);
 370   output_autoconf(s, o, "autoconf-asm-syscall.c",
 371                   "STAPCONF_ASM_SYSCALL_H", NULL);
 372   output_autoconf(s, o, "autoconf-ring_buffer-flags.c", "STAPCONF_RING_BUFFER_FLAGS", NULL);
 373   output_autoconf(s, o, "autoconf-ring_buffer_lost_events.c", "STAPCONF_RING_BUFFER_LOST_EVENTS", NULL);
 374   output_autoconf(s, o, "autoconf-ring_buffer_read_prepare.c", "STAPCONF_RING_BUFFER_READ_PREPARE", NULL);
 375   output_autoconf(s, o, "autoconf-kallsyms-on-each-symbol.c", "STAPCONF_KALLSYMS_ON_EACH_SYMBOL", NULL);
 376   output_autoconf(s, o, "autoconf-walk-stack.c", "STAPCONF_WALK_STACK", NULL);
 377   output_autoconf(s, o, "autoconf-stacktrace_ops-warning.c",
 378                   "STAPCONF_STACKTRACE_OPS_WARNING", NULL);
 379   output_autoconf(s, o, "autoconf-mm-context-vdso.c", "STAPCONF_MM_CONTEXT_VDSO", NULL);
 380   output_autoconf(s, o, "autoconf-mm-context-vdso-base.c", "STAPCONF_MM_CONTEXT_VDSO_BASE", NULL);
 381   output_autoconf(s, o, "autoconf-blk-types.c", "STAPCONF_BLK_TYPES", NULL);
 382   output_autoconf(s, o, "autoconf-perf-structpid.c", "STAPCONF_PERF_STRUCTPID", NULL);
 383   output_autoconf(s, o, "perf_event_counter_context.c",
 384                   "STAPCONF_PERF_COUNTER_CONTEXT", NULL);
 385   output_autoconf(s, o, "perf_probe_handler_nmi.c",
 386                   "STAPCONF_PERF_HANDLER_NMI", NULL);
 387   output_exportconf(s, o, "path_lookup", "STAPCONF_PATH_LOOKUP");
 388   output_exportconf(s, o, "kern_path_parent", "STAPCONF_KERN_PATH_PARENT");
 389   output_exportconf(s, o, "vfs_path_lookup", "STAPCONF_VFS_PATH_LOOKUP");
 390   output_exportconf(s, o, "kern_path", "STAPCONF_KERN_PATH");
 391   output_exportconf(s, o, "proc_create_data", "STAPCONF_PROC_CREATE_DATA");
 392   output_exportconf(s, o, "PDE_DATA", "STAPCONF_PDE_DATA");
 393   output_autoconf(s, o, "autoconf-module-sect-attrs.c", "STAPCONF_MODULE_SECT_ATTRS", NULL);
 394
 395   output_autoconf(s, o, "autoconf-utrace-via-tracepoints.c", "STAPCONF_UTRACE_VIA_TRACEPOINTS", NULL);
 396   output_autoconf(s, o, "autoconf-task_work-struct.c", "STAPCONF_TASK_WORK_STRUCT", NULL);
 397   output_autoconf(s, o, "autoconf-vm-area-pte.c", "STAPCONF_VM_AREA_PTE", NULL);
 398   output_autoconf(s, o, "autoconf-relay-umode_t.c", "STAPCONF_RELAY_UMODE_T", NULL);
 399   output_autoconf(s, o, "autoconf-fs_supers-hlist.c", "STAPCONF_FS_SUPERS_HLIST", NULL);
 400   output_autoconf(s, o, "autoconf-compat_sigaction.c", "STAPCONF_COMPAT_SIGACTION", NULL);
 401   output_autoconf(s, o, "autoconf-netfilter.c", "STAPCONF_NETFILTER_V313", NULL);
 402   output_autoconf(s, o, "autoconf-netfilter-313b.c", "STAPCONF_NETFILTER_V313B", NULL);
 403   output_autoconf(s, o, "autoconf-netfilter-4_1.c", "STAPCONF_NETFILTER_V41", NULL);
 404   output_autoconf(s, o, "autoconf-netfilter-4_4.c", "STAPCONF_NETFILTER_V44", NULL);
 405   output_autoconf(s, o, "autoconf-smpcall-5args.c", "STAPCONF_SMPCALL_5ARGS", NULL);
 406   output_autoconf(s, o, "autoconf-smpcall-4args.c", "STAPCONF_SMPCALL_4ARGS", NULL);
 407
 408   // used by tapset/timestamp_monotonic.stp
 409   output_exportconf(s, o, "cpu_clock", "STAPCONF_CPU_CLOCK");
 410   output_exportconf(s, o, "local_clock", "STAPCONF_LOCAL_CLOCK");
 411
 412   // used by runtime/uprobe-inode.c
 413   output_either_exportconf(s, o, "uprobe_register", "register_uprobe",
 414                            "STAPCONF_UPROBE_REGISTER_EXPORTED");
 415   output_either_exportconf(s, o, "uprobe_unregister", "unregister_uprobe",
 416                            "STAPCONF_UPROBE_UNREGISTER_EXPORTED");
 417   output_autoconf(s, o, "autoconf-old-inode-uprobes.c", "STAPCONF_OLD_INODE_UPROBES", NULL);
 418   output_autoconf(s, o, "autoconf-inode-uretprobes.c", "STAPCONF_INODE_URETPROBES", NULL);
 419
 420   // used by tapsets.cxx inode uprobe generated code
 421   output_exportconf(s, o, "uprobe_get_swbp_addr", "STAPCONF_UPROBE_GET_SWBP_ADDR_EXPORTED");
 422
 423   // used by runtime/loc2c-runtime.h
 424   output_exportconf(s, o, "task_user_regset_view", "STAPCONF_TASK_USER_REGSET_VIEW_EXPORTED");
 425
 426   // used by runtime/stp_utrace.c
 427   output_exportconf(s, o, "task_work_add", "STAPCONF_TASK_WORK_ADD_EXPORTED");
 428   output_exportconf(s, o, "wake_up_state", "STAPCONF_WAKE_UP_STATE_EXPORTED");
 429   output_exportconf(s, o, "try_to_wake_up", "STAPCONF_TRY_TO_WAKE_UP_EXPORTED");
 430   output_exportconf(s, o, "signal_wake_up_state", "STAPCONF_SIGNAL_WAKE_UP_STATE_EXPORTED");
 431   output_exportconf(s, o, "signal_wake_up", "STAPCONF_SIGNAL_WAKE_UP_EXPORTED");
 432   output_exportconf(s, o, "__lock_task_sighand", "STAPCONF___LOCK_TASK_SIGHAND_EXPORTED");
 433
 434   output_autoconf(s, o, "autoconf-pagefault_disable.c", "STAPCONF_PAGEFAULT_DISABLE", NULL);
 435   output_exportconf(s, o, "kallsyms_lookup_name", "STAPCONF_KALLSYMS");
 436   output_autoconf(s, o, "autoconf-uidgid.c", "STAPCONF_LINUX_UIDGID_H", NULL);
 437   output_exportconf(s, o, "sigset_from_compat", "STAPCONF_SIGSET_FROM_COMPAT_EXPORTED");
 438   output_exportconf(s, o, "vzalloc", "STAPCONF_VZALLOC");
 439   output_exportconf(s, o, "vzalloc_node", "STAPCONF_VZALLOC_NODE");
 440   output_exportconf(s, o, "vmalloc_node", "STAPCONF_VMALLOC_NODE");
 441
 442   // RHBZ1233912 - s390 temporary workaround for non-atomic udelay()
 443   output_exportconf(s, o, "udelay_simple", "STAPCONF_UDELAY_SIMPLE");
 444
 445   output_autoconf(s, o, "autoconf-tracepoint-strings.c", "STAPCONF_TRACEPOINT_STRINGS", NULL);
 446   output_autoconf(s, o, "autoconf-timerfd.c", "STAPCONF_TIMERFD_H", NULL);
 447
 448   output_autoconf(s, o, "autoconf-module_layout.c",
 449                   "STAPCONF_MODULE_LAYOUT", NULL);
 450   output_autoconf(s, o, "autoconf-mod_kallsyms.c",
 451                   "STAPCONF_MOD_KALLSYMS", NULL);
 452
 453   o << module_cflags << " += -include $(STAPCONF_HEADER)" << endl;
 454
 455   for (unsigned i=0; i<s.c_macros.size(); i++)
 456     o << "EXTRA_CFLAGS += -D " << lex_cast_qstring(s.c_macros[i]) << endl; // XXX right quoting?
 457
 458   if (s.verbose > 3)
 459     o << "EXTRA_CFLAGS += -ftime-report -Q" << endl;
 460
 461   // XXX: unfortunately, -save-temps can't work since linux kbuild cwd
 462   // is not writable.
 463   //
 464   // if (s.keep_tmpdir)
 465   // o << "CFLAGS += -fverbose-asm -save-temps" << endl;
 466
 467   // Kernels can be compiled with CONFIG_CC_OPTIMIZE_FOR_SIZE to select
 468   // -Os, otherwise -O2 is the default.
 469   o << "EXTRA_CFLAGS += -freorder-blocks" << endl; // improve on -Os
 470
 471   // Generate eh_frame for self-backtracing
 472   o << "EXTRA_CFLAGS += -fasynchronous-unwind-tables" << endl;
 473
 474   // We used to allow the user to override default optimization when so
 475   // requested by adding a -O[0123s] so they could determine the
 476   // time/space/speed tradeoffs themselves, but we cannot guantantee that
 477   // the (un)optimized code actually compiles and/or generates functional
 478   // code, so we had to remove it.
 479   // o << "EXTRA_CFLAGS += " << s.gcc_flags << endl; // Add -O[0123s]
 480
 481   // o << "CFLAGS += -fno-unit-at-a-time" << endl;
 482
 483   // 256^W512 bytes should be enough for anybody
 484   // XXX this doesn't validate varargs, per gcc bug #41633
 485   o << "EXTRA_CFLAGS += $(call cc-option,-Wframe-larger-than=512)" << endl;
 486
 487   // gcc 5.0.0-0.13.fc23 ipa-icf seems to consume gigacpu on stap-generated code
 488   o << "EXTRA_CFLAGS += $(call cc-option,-fno-ipa-icf)" << endl;
 489
 490   // Assumes linux 2.6 kbuild
 491   o << "EXTRA_CFLAGS += -Wno-unused " << WERROR << endl;
 492   #if CHECK_POINTER_ARITH_PR5947
 493   o << "EXTRA_CFLAGS += -Wpointer-arith" << endl;
 494   #endif
 495   o << "EXTRA_CFLAGS += -I\"" << s.runtime_path << "\"" << endl;
 496   // XXX: this may help ppc toc overflow
 497   // o << "CFLAGS := $(subst -Os,-O2,$(CFLAGS)) -fminimal-toc" << endl;
 498   o << "obj-m := " << s.module_name << ".o" << endl;
 499
 500   // print out all the auxiliary source (->object) file names
 501   o << s.module_name << "-y := ";
 502   for (unsigned i=0; i<s.auxiliary_outputs.size(); i++)
 503     {
 504       if (s.auxiliary_outputs[i]->trailer_p) continue;
 505       string srcname = s.auxiliary_outputs[i]->filename;
 506       assert (srcname != "" && srcname.rfind('/') != string::npos);
 507       string objname = srcname.substr(srcname.rfind('/')+1); // basename
 508       assert (objname != "" && objname[objname.size()-1] == 'c');
 509       objname[objname.size()-1] = 'o'; // now objname
 510       o << " " + objname;
 511     }
 512   // and once again, for the translated_source file.  It can't simply
 513   // be named MODULENAME.c, since kbuild doesn't allow a foo.ko file
 514   // consisting of multiple .o's to have foo.o/foo.c as a source.
 515   // (It uses ld -r -o foo.o EACH.o EACH.o).
 516   {
 517     string srcname = s.translated_source;
 518     assert (srcname != "" && srcname.rfind('/') != string::npos);
 519     string objname = srcname.substr(srcname.rfind('/')+1); // basename
 520     assert (objname != "" && objname[objname.size()-1] == 'c');
 521     objname[objname.size()-1] = 'o'; // now objname
 522     o << " " + objname;
 523   }
 524   // and once again, for the trailer type auxiliary outputs.
 525   for (unsigned i=0; i<s.auxiliary_outputs.size(); i++)
 526     {
 527       if (! s.auxiliary_outputs[i]->trailer_p) continue;
 528       string srcname = s.auxiliary_outputs[i]->filename;
 529       assert (srcname != "" && srcname.rfind('/') != string::npos);
 530       string objname = srcname.substr(srcname.rfind('/')+1); // basename
 531       assert (objname != "" && objname[objname.size()-1] == 'c');
 532       objname[objname.size()-1] = 'o'; // now objname
 533       o << " " + objname;
 534     }
 535   o << endl;
 536
 537   // add all stapconf dependencies
 538   o << s.translated_source << ": $(STAPCONF_HEADER)" << endl;
 539   for (unsigned i=0; i<s.auxiliary_outputs.size(); i++)
 540     o << s.auxiliary_outputs[i]->filename << ": $(STAPCONF_HEADER)" << endl;
 541
 542
 543   o.close ();
 544
 545   // Generate module directory pathname and make sure it exists.
 546   string module_dir = s.kernel_build_tree;
 547   string module_dir_makefile = module_dir + "/Makefile";
 548   struct stat st;
 549   rc = stat(module_dir_makefile.c_str(), &st);
 550   if (rc != 0)
 551     {
 552         clog << _F("Checking \" %s \" failed with error: %s\nEnsure kernel development headers & makefiles are installed.",
 553                    module_dir_makefile.c_str(), strerror(errno)) << endl;
 554         s.set_try_server ();
 555         return rc;
 556     }
 557
 558   // Run make
 559   vector<string> make_cmd = make_make_cmd(s, s.tmpdir);
 560   rc = run_make_cmd(s, make_cmd);
 561   if (rc)
 562     s.set_try_server ();
 563   return rc;
 564 }
 565
 566 /*
 567  * If uprobes was built as part of the kernel build (either built-in
 568  * or as a module), the uprobes exports should show up.  This is to be
 569  * as distinct from the stap-built uprobes.ko from the runtime.
 570  */
 571 static bool
 572 kernel_built_uprobes (systemtap_session& s)
 573 {
 574   if (s.runtime_usermode_p())
 575     return true; // sort of, via dyninst
 576
 577   // see also tapsets.cxx:kernel_supports_inode_uprobes()
 578   return ((s.kernel_config["CONFIG_ARCH_SUPPORTS_UPROBES"] == "y" && s.kernel_config["CONFIG_UPROBES"] == "y") ||
 579           (s.kernel_exports.find("unregister_uprobe") != s.kernel_exports.end()));
 580 }
 581
 582 static int
 583 make_uprobes (systemtap_session& s)
 584 {
 585   if (s.verbose > 1)
 586     clog << _("Pass 4, preamble: (re)building SystemTap's version of uprobes.")
 587          << endl;
 588
 589   // create a subdirectory for the uprobes module
 590   string dir(s.tmpdir + "/uprobes");
 591   if (create_dir(dir.c_str()) != 0)
 592     {
 593       s.print_warning("failed to create directory for build uprobes.");
 594       s.set_try_server ();
 595       return 1;
 596     }
 597
 598   // create a simple Makefile
 599   string makefile(dir + "/Makefile");
 600   ofstream omf(makefile.c_str());
 601   omf << "obj-m := uprobes.o" << endl;
 602   // RHBZ 655231: later rhel6 kernels' module-signing kbuild logic breaks out-of-tree modules
 603   omf << "CONFIG_MODULE_SIG := n" << endl;
 604   omf.close();
 605
 606   // create a simple #include-chained source file
 607   string runtimesourcefile(s.runtime_path + "/linux/uprobes/uprobes.c");
 608   string sourcefile(dir + "/uprobes.c");
 609   ofstream osrc(sourcefile.c_str());
 610   osrc << "#include \"" << runtimesourcefile << "\"" << endl;
 611
 612   // pass --modinfo k=v to uprobes build too
 613   for (unsigned i = 0; i < s.modinfos.size(); i++)
 614     {
 615       const string& mi = s.modinfos[i];
 616       size_t loc = mi.find('=');
 617       string tag = mi.substr (0, loc);
 618       string value = mi.substr (loc+1);
 619       osrc << "MODULE_INFO(" << tag << "," << lex_cast_qstring(value) << ");" << endl;
 620     }
 621
 622   osrc.close();
 623
 624   // make the module
 625   vector<string> make_cmd = make_make_cmd(s, dir);
 626   int rc = run_make_cmd(s, make_cmd);
 627   if (!rc && !copy_file(dir + "/Module.symvers",
 628                         s.tmpdir + "/Module.symvers"))
 629     rc = -1;
 630
 631   if (s.verbose > 1)
 632     clog << _("uprobes rebuild exit code: ") << rc << endl;
 633   if (rc)
 634     s.set_try_server ();
 635   else
 636     s.uprobes_path = dir + "/uprobes.ko";
 637   return rc;
 638 }
 639
 640 static bool
 641 get_cached_uprobes(systemtap_session& s)
 642 {
 643   s.uprobes_hash = s.use_cache ? find_uprobes_hash(s) : "";
 644   if (!s.uprobes_hash.empty())
 645     {
 646       // NB: We always put uprobes.ko in its own directory, especially so
 647       // stap-serverd can more easily locate it.
 648       string dir(s.tmpdir + "/uprobes");
 649       if (create_dir(dir.c_str()) != 0)
 650         return false;
 651
 652       string cacheko = s.uprobes_hash + ".ko";
 653       string tmpko = dir + "/uprobes.ko";
 654
 655       // The symvers file still needs to go in the script module's directory.
 656       string cachesyms = s.uprobes_hash + ".symvers";
 657       string tmpsyms = s.tmpdir + "/Module.symvers";
 658
 659       if (get_file_size(cacheko) > 0 && copy_file(cacheko, tmpko) &&
 660           get_file_size(cachesyms) > 0 && copy_file(cachesyms, tmpsyms))
 661         {
 662           s.uprobes_path = tmpko;
 663           return true;
 664         }
 665     }
 666   return false;
 667 }
 668
 669 static void
 670 set_cached_uprobes(systemtap_session& s)
 671 {
 672   if (s.use_cache && !s.uprobes_hash.empty())
 673     {
 674       string cacheko = s.uprobes_hash + ".ko";
 675       string tmpko = s.tmpdir + "/uprobes/uprobes.ko";
 676       copy_file(tmpko, cacheko);
 677
 678       string cachesyms = s.uprobes_hash + ".symvers";
 679       string tmpsyms = s.tmpdir + "/uprobes/Module.symvers";
 680       copy_file(tmpsyms, cachesyms);
 681     }
 682 }
 683
 684 int
 685 uprobes_pass (systemtap_session& s)
 686 {
 687   if (!s.need_uprobes || kernel_built_uprobes(s))
 688     return 0;
 689
 690   if (s.kernel_config["CONFIG_UTRACE"] != string("y"))
 691     {
 692       clog << _("user-space process-tracking facilities not available [man error::process-tracking]") << endl;
 693       s.set_try_server ();
 694       return 1;
 695     }
 696
 697   /*
 698    * We need to use the version of uprobes that comes with SystemTap.  Try to
 699    * get it from the cache first.  If not found, build it and try to save it to
 700    * the cache for future reuse.
 701    */
 702   int rc = 0;
 703   if (!get_cached_uprobes(s))
 704     {
 705       rc = make_uprobes(s);
 706       if (!rc)
 707         set_cached_uprobes(s);
 708     }
 709   if (rc)
 710     s.set_try_server ();
 711   return rc;
 712 }
 713
 714 static
 715 vector<string>
 716 make_dyninst_run_command (systemtap_session& s, const string& remotedir,
 717                           const string&)
 718 {
 719   vector<string> cmd;
 720   cmd.push_back(getenv("SYSTEMTAP_STAPDYN") ?: BINDIR "/stapdyn");
 721
 722   // use slightly less verbosity
 723   for (unsigned i=1; i<s.verbose; i++)
 724     cmd.push_back("-v");
 725   if (s.suppress_warnings)
 726     cmd.push_back("-w");
 727
 728   if (!s.cmd.empty())
 729     {
 730       cmd.push_back("-c");
 731       cmd.push_back(s.cmd);
 732     }
 733
 734   if (s.target_pid)
 735     {
 736       cmd.push_back("-x");
 737       cmd.push_back(lex_cast(s.target_pid));
 738     }
 739
 740   if (!s.output_file.empty())
 741     {
 742       cmd.push_back("-o");
 743       cmd.push_back(s.output_file);
 744     }
 745
 746   if (s.color_mode != s.color_auto)
 747     {
 748       cmd.push_back("-C");
 749       if (s.color_mode == s.color_always)
 750         cmd.push_back("always");
 751       else
 752         cmd.push_back("never");
 753     }
 754
 755   cmd.push_back((remotedir.empty() ? s.tmpdir : remotedir)
 756                 + "/" + s.module_filename());
 757
 758   // add module arguments
 759   cmd.insert(cmd.end(), s.globalopts.begin(), s.globalopts.end());
 760
 761   return cmd;
 762 }
 763
 764 vector<string>
 765 make_run_command (systemtap_session& s, const string& remotedir,
 766                   const string& version)
 767 {
 768   if (s.runtime_usermode_p())
 769     return make_dyninst_run_command(s, remotedir, version);
 770
 771   // for now, just spawn staprun
 772   vector<string> staprun_cmd;
 773   staprun_cmd.push_back(getenv("SYSTEMTAP_STAPRUN") ?: BINDIR "/staprun");
 774
 775   // use slightly less verbosity
 776   for (unsigned i=1; i<s.verbose; i++)
 777     staprun_cmd.push_back("-v");
 778   if (s.suppress_warnings)
 779     staprun_cmd.push_back("-w");
 780
 781   if (!s.output_file.empty())
 782     {
 783       staprun_cmd.push_back("-o");
 784       staprun_cmd.push_back(s.output_file);
 785     }
 786
 787   if (!s.cmd.empty())
 788     {
 789       staprun_cmd.push_back("-c");
 790       staprun_cmd.push_back(s.cmd);
 791     }
 792
 793   if (s.target_pid)
 794     {
 795       staprun_cmd.push_back("-t");
 796       staprun_cmd.push_back(lex_cast(s.target_pid));
 797     }
 798
 799   if (s.target_namespaces_pid)
 800     {
 801       staprun_cmd.push_back("-N");
 802       staprun_cmd.push_back(lex_cast(s.target_namespaces_pid));
 803     }
 804
 805   if (s.buffer_size)
 806     {
 807       staprun_cmd.push_back("-b");
 808       staprun_cmd.push_back(lex_cast(s.buffer_size));
 809     }
 810
 811   if (s.need_uprobes && !kernel_built_uprobes(s))
 812     {
 813       string opt_u = "-u";
 814       if (!s.uprobes_path.empty() &&
 815           strverscmp("1.4", version.c_str()) <= 0)
 816         {
 817           if (remotedir.empty())
 818             opt_u.append(s.uprobes_path);
 819           else
 820             opt_u.append(remotedir + "/" + basename(s.uprobes_path.c_str()));
 821         }
 822       staprun_cmd.push_back(opt_u);
 823     }
 824
 825   if (s.load_only)
 826     staprun_cmd.push_back(s.output_file.empty() ? "-L" : "-D");
 827
 828   // Note that if this system requires signed modules, we can't rename
 829   // it after it has been signed.
 830   if (!s.modname_given && (strverscmp("1.6", version.c_str()) <= 0)
 831       && s.mok_fingerprints.empty())
 832     staprun_cmd.push_back("-R");
 833
 834   if (!s.size_option.empty())
 835     {
 836       staprun_cmd.push_back("-S");
 837       staprun_cmd.push_back(s.size_option);
 838     }
 839
 840   if (s.color_mode != s.color_auto)
 841     {
 842       staprun_cmd.push_back("-C");
 843       if (s.color_mode == s.color_always)
 844         staprun_cmd.push_back("always");
 845       else
 846         staprun_cmd.push_back("never");
 847     }
 848
 849   if (s.monitor)
 850     {
 851       staprun_cmd.push_back("-M");
 852       staprun_cmd.push_back(lex_cast(s.monitor_interval));
 853     }
 854
 855   staprun_cmd.push_back((remotedir.empty() ? s.tmpdir : remotedir)
 856                         + "/" + s.module_filename());
 857
 858   // add module arguments
 859   staprun_cmd.insert(staprun_cmd.end(),
 860                      s.globalopts.begin(), s.globalopts.end());
 861
 862   return staprun_cmd;
 863 }
 864
 865
 866 // Build tiny kernel modules to query tracepoints.
 867 // Given a (header-file -> test-contents) map, compile them ASAP, and return
 868 // a (header-file -> obj-filename) map.
 869
 870 map<string,string>
 871 make_tracequeries(systemtap_session& s, const map<string,string>& contents)
 872 {
 873   static unsigned tick = 0;
 874   string basename("tracequery_kmod_" + lex_cast(++tick));
 875   map<string,string> objs;
 876
 877   // create a subdirectory for the module
 878   string dir(s.tmpdir + "/" + basename);
 879   if (create_dir(dir.c_str()) != 0)
 880     {
 881       s.print_warning("failed to create directory for querying tracepoints.");
 882       s.set_try_server ();
 883       return objs;
 884     }
 885
 886   // create a simple Makefile
 887   string makefile(dir + "/Makefile");
 888   ofstream omf(makefile.c_str());
 889   // force debuginfo generation, and relax implicit functions
 890   omf << "EXTRA_CFLAGS := -g -Wno-implicit-function-declaration " << WERROR << endl;
 891   // RHBZ 655231: later rhel6 kernels' module-signing kbuild logic breaks out-of-tree modules
 892   omf << "CONFIG_MODULE_SIG := n" << endl;
 893
 894   // PR18389: disable GCC's Identical Code Folding, since the stubs may look identical
 895   omf << "EXTRA_CFLAGS += $(call cc-option,-fno-ipa-icf)" << endl;
 896
 897   omf << "EXTRA_CFLAGS += -I" + s.kernel_build_tree << endl;
 898   if (s.kernel_source_tree != "")
 899     omf << "EXTRA_CFLAGS += -I" + s.kernel_source_tree << endl;
 900   for (unsigned i = 0; i < s.kernel_extra_cflags.size(); i++)
 901     omf << "EXTRA_CFLAGS += " + s.kernel_extra_cflags[i] << endl;
 902
 903   omf << "obj-m := " << endl;
 904   // write out each header-specific source file into a separate file
 905   for (map<string,string>::const_iterator it = contents.begin(); it != contents.end(); it++)
 906     {
 907       string sbasename = basename + "_" + lex_cast(++tick); // suffixed
 908
 909       // write out source code
 910       string srcname = dir + "/" + sbasename + ".c";
 911       string src = it->second;
 912       ofstream osrc(srcname.c_str());
 913       osrc << src;
 914       osrc.close();
 915
 916       if (s.verbose > 2)
 917         clog << _F("Processing tracepoint header %s with query %s",
 918                    it->first.c_str(), srcname.c_str())
 919              << endl;
 920
 921       // arrange to build it
 922       omf << "obj-m += " + sbasename + ".o" << endl; // NB: without <dir> prefix
 923       objs[it->first] = dir + "/" + sbasename + ".o";
 924     }
 925   omf.close();
 926
 927   // make the module
 928   vector<string> make_cmd = make_make_objs_cmd(s, dir);
 929   make_cmd.push_back ("-i"); // ignore errors, give rc 0 even in case of tracepoint header nits
 930   bool quiet = (s.verbose < 4);
 931   int rc = run_make_cmd(s, make_cmd, quiet, quiet);
 932   if (rc)
 933     s.set_try_server ();
 934
 935   // Sometimes we fail a tracequery due to PR9993 / PR11649 type
 936   // kernel trace header problems.  In this case, due to PR12729, we
 937   // used to get a lovely "Warning: make exited with status: 2" but no
 938   // other useful diagnostic.  -vvvv would let a user see what's up,
 939   // but the user can't fix the problem even with that.
 940
 941   return objs;
 942 }
 943
 944
 945 // Build a tiny kernel module to query type information
 946 static int
 947 make_typequery_kmod(systemtap_session& s, const vector<string>& headers, string& name)
 948 {
 949   static unsigned tick = 0;
 950   string basename("typequery_kmod_" + lex_cast(++tick));
 951
 952   // create a subdirectory for the module
 953   string dir(s.tmpdir + "/" + basename);
 954   if (create_dir(dir.c_str()) != 0)
 955     {
 956       s.print_warning("failed to create directory for querying types.");
 957       s.set_try_server ();
 958       return 1;
 959     }
 960
 961   name = dir + "/" + basename + ".ko";
 962
 963   // create a simple Makefile
 964   string makefile(dir + "/Makefile");
 965   ofstream omf(makefile.c_str());
 966   omf << "EXTRA_CFLAGS := -g -fno-eliminate-unused-debug-types" << endl;
 967
 968   // RHBZ 655231: later rhel6 kernels' module-signing kbuild logic breaks out-of-tree modules
 969   omf << "CONFIG_MODULE_SIG := n" << endl;
 970
 971   // NB: We use -include instead of #include because that gives us more power.
 972   // Using #include searches relative to the source's path, which in this case
 973   // is /tmp/..., so that's not helpful.  Using -include will search relative
 974   // to the cwd, which will be the kernel build root.  This means if you have a
 975   // full kernel build tree, it's possible to get at types that aren't in the
 976   // normal include path, e.g.:
 977   //    @cast(foo, "bsd_acct_struct", "kernel<kernel/acct.c>")->...
 978   omf << "CFLAGS_" << basename << ".o :=";
 979   for (size_t i = 0; i < headers.size(); ++i)
 980     omf << " -include " << lex_cast_qstring(headers[i]); // XXX right quoting?
 981   omf << endl;
 982
 983   omf << "obj-m := " + basename + ".o" << endl;
 984   omf.close();
 985
 986   // create our empty source file
 987   string source(dir + "/" + basename + ".c");
 988   ofstream osrc(source.c_str());
 989   osrc.close();
 990
 991   // make the module
 992   vector<string> make_cmd = make_make_cmd(s, dir);
 993   bool quiet = (s.verbose < 4);
 994   int rc = run_make_cmd(s, make_cmd, quiet, quiet);
 995   if (rc)
 996     s.set_try_server ();
 997   return rc;
 998 }
 999
1000
1001 // Build a tiny user module to query type information
1002 static int
1003 make_typequery_umod(systemtap_session& s, const vector<string>& headers, string& name)
1004 {
1005   static unsigned tick = 0;
1006
1007   name = s.tmpdir + "/typequery_umod_" + lex_cast(++tick) + ".so";
1008
1009   // make the module
1010   //
1011   // NB: As with kmod, using -include makes relative paths more useful.  The
1012   // cwd in this case will be the cwd of stap itself though, which may be
1013   // trickier to deal with.  It might be better to "cd `dirname $script`"
1014   // first...
1015   vector<string> cmd;
1016   cmd.push_back("gcc");
1017   cmd.push_back("-shared");
1018   cmd.push_back("-g");
1019   cmd.push_back("-fno-eliminate-unused-debug-types");
1020   cmd.push_back("-xc");
1021   cmd.push_back("/dev/null");
1022   cmd.push_back("-o");
1023   cmd.push_back(name);
1024   for (size_t i = 0; i < headers.size(); ++i)
1025     {
1026       cmd.push_back("-include");
1027       cmd.push_back(headers[i]);
1028     }
1029   bool quiet = (s.verbose < 4);
1030   int rc = stap_system (s.verbose, cmd, quiet, quiet);
1031   if (rc)
1032     s.set_try_server ();
1033   return rc;
1034 }
1035
1036
1037 int
1038 make_typequery(systemtap_session& s, string& module)
1039 {
1040   int rc;
1041   string new_module;
1042   vector<string> headers;
1043   bool kernel = startswith(module, "kernel");
1044
1045   for (size_t end, i = kernel ? 6 : 0; i < module.size(); i = end + 1)
1046     {
1047       if (module[i] != '<')
1048         return -1;
1049       end = module.find('>', ++i);
1050       if (end == string::npos)
1051         return -1;
1052       string header = module.substr(i, end - i);
1053       vector<string> matches;
1054       if (regexp_match(header, "^[a-zA-Z0-9/_.+-]+$", matches))
1055         s.print_warning("skipping malformed @cast header \""+ header + "\"");
1056       else
1057         headers.push_back(header);
1058     }
1059   if (headers.empty())
1060     return -1;
1061
1062   if (kernel)
1063       rc = make_typequery_kmod(s, headers, new_module);
1064   else
1065       rc = make_typequery_umod(s, headers, new_module);
1066
1067   if (!rc)
1068     module = new_module;
1069
1070   return rc;
1071 }
1072
1073 /* vim: set sw=2 ts=8 cino=>4,n-2,{2,^-2,t0,(0,u0,w1,M1 : */