/*

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 *

 */

#ifdef HAVE_DTRACE_H

#include <sys/types.h>

#include <sys/stat.h>

#include <fcntl.h>

#include <unistd.h>

#include <dtrace.h>

static const char* devname    = "/dev/dtrace/helper";

static const char* olddevname = "/devices/pseudo/dtrace@0:helper";

static const char* string_sig = "uintptr_t";

static const char* int_sig    = "long";

static const char* long_sig   = "long long";

static void printDOFHelper(dof_helper_t* helper);

static int dofhelper_open() {

  int fd;

  if ((fd = open64(devname, O_RDWR)) < 0) {

    // Optimize next calls

    devname = olddevname;

    if ((fd = open64(devname, O_RDWR)) < 0) {

      return -1;

    }

  }

  return fd;

}

static jint dof_register(jstring module, uint8_t* dof, void* modaddr) {

  int probe;

  dof_helper_t dh;

  int fd;

  memset(&dh, 0, sizeof(dh));

  char* module_name = java_lang_String::as_utf8_string(

        JNIHandles::resolve_non_null(module));

  jio_snprintf(dh.dofhp_mod, sizeof(dh.dofhp_mod), "%s", module_name);

  dh.dofhp_dof  = (uint64_t)dof;

  dh.dofhp_addr = (uint64_t)modaddr;

  fd = dofhelper_open();

  if (fd < 0)

    return -1;

  probe = ioctl(fd, DTRACEHIOC_ADDDOF, &dh);

  close(fd);

  if (PrintDTraceDOF) {

    printDOFHelper(&dh);

    tty->print_cr("DOF helper id = %d", probe);

  }

  return probe;

}

int DTraceJSDT::pd_activate(

    void* moduleBaseAddress, jstring module,

    jint providers_count, JVM_DTraceProvider* providers) {

  // We need sections:

  //  (1) STRTAB

  //  (

  //    (2) PROVIDER

  //    (3) PROBES

  //    (4) PROBOFFS

  //    (5) PROBARGS

  //  ) * Number of Providers

  // Type of sections we create

  enum {

    STRTAB = 0,

    PROVIDERS = 1,

    PROBES = 2,

    PROBE_OFFSETS = 3,

    ARG_OFFSETS = 4,

    NUM_SECTIONS = 5

  };

  static int alignment_for[NUM_SECTIONS] = { 1, 4, 8, 4, 1 };

  ResourceMark rm;

  uint32_t num_sections = 1 + 4 * providers_count;

  uint32_t offset = sizeof(dof_hdr_t) + (num_sections * sizeof(dof_sec_t));

  uint32_t* secoffs = NEW_RESOURCE_ARRAY(uint32_t, num_sections);

  uint32_t* secsize = NEW_RESOURCE_ARRAY(uint32_t, num_sections);

  // Store offsets of all strings here in such order:

  //  zero-string (always 0)

  //  provider1-name

  //    probe1-function

  //    probe1-name

  //    arg-1

  //    arg-2

  //    ...

  //    probe2-function

  //    probe2-name

  //    arg-1

  //    arg-2

  //  provider2-name

  //    ...

  uint32_t strcount  = 0;

  // Count the number of strings we'll need

  for(int prvc = 0; prvc < providers_count; ++prvc) {

    JVM_DTraceProvider* provider = &providers[prvc];

    // Provider name

    ++strcount;

    for(int prbc = 0; prbc < provider->probe_count; ++prbc) {

      JVM_DTraceProbe* p = &(provider->probes[prbc]);

      symbolOop sig = JNIHandles::resolve_jmethod_id(p->method)->signature();

      // function + name + one per argument

      strcount += 2 + ArgumentCount(sig).size();

    }

  }

  // Create place for string offsets

  uint32_t* stroffs = NEW_RESOURCE_ARRAY(uint32_t, strcount + 1);

  uint32_t string_index = 0;

  uint32_t curstr = 0;

  // First we need an empty string: ""

  stroffs[curstr++] = string_index;

  string_index += strlen("") + 1;

  for(int prvc = 0; prvc < providers_count; ++prvc) {

    JVM_DTraceProvider* provider = &providers[prvc];

    char* provider_name = java_lang_String::as_utf8_string(

        JNIHandles::resolve_non_null(provider->name));

    stroffs[curstr++] = string_index;

    string_index += strlen(provider_name) + 1;

    // All probes

    for(int prbc = 0; prbc < provider->probe_count; ++prbc) {

      JVM_DTraceProbe* p = &(provider->probes[prbc]);

      char* function = java_lang_String::as_utf8_string(

          JNIHandles::resolve_non_null(p->function));

      stroffs[curstr++] = string_index;

      string_index += strlen(function) + 1;

      char* name = java_lang_String::as_utf8_string(

          JNIHandles::resolve_non_null(p->name));

      stroffs[curstr++] = string_index;

      string_index += strlen(name) + 1;

      symbolOop sig = JNIHandles::resolve_jmethod_id(p->method)->signature();

      SignatureStream ss(sig);

      for ( ; !ss.at_return_type(); ss.next()) {

        BasicType bt = ss.type();

        const char* t = NULL;

        if (bt == T_OBJECT &&

            ss.as_symbol_or_null() == vmSymbols::java_lang_String()) {

          t = string_sig;

        } else if (bt == T_LONG) {

          t = long_sig;

        } else {

          t = int_sig;

        }

        stroffs[curstr++] = string_index;

        string_index += strlen(t) + 1;

      }

    }

  }

  secoffs[STRTAB] = offset;

  secsize[STRTAB] = string_index;

  offset += string_index;

  // Calculate the size of the rest

  for(int prvc = 0; prvc < providers_count; ++prvc) {

    JVM_DTraceProvider* provider = &providers[prvc];

    size_t provider_sec  = PROVIDERS     + prvc * 4;

    size_t probe_sec     = PROBES        + prvc * 4;

    size_t probeoffs_sec = PROBE_OFFSETS + prvc * 4;

    size_t argoffs_sec   = ARG_OFFSETS   + prvc * 4;

    // Allocate space for the provider data struction

    secoffs[provider_sec] = align_size_up(offset, alignment_for[PROVIDERS]);

    secsize[provider_sec] = sizeof(dof_provider_t);

    offset = secoffs[provider_sec] + secsize[provider_sec];

    // Allocate space for all the probes

    secoffs[probe_sec] = align_size_up(offset, alignment_for[PROBES]);

    secsize[probe_sec] = sizeof(dof_probe_t) * provider->probe_count;

    offset = secoffs[probe_sec] + secsize[probe_sec];

    // Allocate space for the probe offsets

    secoffs[probeoffs_sec] = align_size_up(offset, alignment_for[PROBE_OFFSETS]);

    secsize[probeoffs_sec] = sizeof(uint32_t) * provider->probe_count;

    offset = secoffs[probeoffs_sec] + secsize[probeoffs_sec];

    // We need number of arguments argoffs

    uint32_t argscount = 0;

    for(int prbc = 0; prbc < provider->probe_count; ++prbc) {

       JVM_DTraceProbe* p = &(provider->probes[prbc]);

       symbolOop sig = JNIHandles::resolve_jmethod_id(p->method)->signature();

       argscount += ArgumentCount(sig).size();

    }

    secoffs[argoffs_sec] = align_size_up(offset, alignment_for[ARG_OFFSETS]);

    secsize[argoffs_sec] = sizeof(uint8_t) * argscount;

    offset = secoffs[argoffs_sec] + secsize[argoffs_sec];

  }

  uint32_t size = offset;

  uint8_t* dof = NEW_RESOURCE_ARRAY(uint8_t, size);

  if (!dof) {

    return -1;

  }

  memset((void*)dof, 0, size);

  // Fill memory with proper values

  dof_hdr_t* hdr = (dof_hdr_t*)dof;

  hdr->dofh_ident[DOF_ID_MAG0]     = DOF_MAG_MAG0;

  hdr->dofh_ident[DOF_ID_MAG1]     = DOF_MAG_MAG1;

  hdr->dofh_ident[DOF_ID_MAG2]     = DOF_MAG_MAG2;

  hdr->dofh_ident[DOF_ID_MAG3]     = DOF_MAG_MAG3;

  hdr->dofh_ident[DOF_ID_MODEL]    = DOF_MODEL_NATIVE;  // No variants

  hdr->dofh_ident[DOF_ID_ENCODING] = DOF_ENCODE_NATIVE; // No variants

  hdr->dofh_ident[DOF_ID_VERSION]  = DOF_VERSION_1;     // No variants

  hdr->dofh_ident[DOF_ID_DIFVERS]  = DIF_VERSION_2;     // No variants

  // all other fields of ident to zero

  hdr->dofh_flags   = 0;

  hdr->dofh_hdrsize = sizeof(dof_hdr_t);

  hdr->dofh_secsize = sizeof(dof_sec_t);

  hdr->dofh_secnum  = num_sections;

  hdr->dofh_secoff  = sizeof(dof_hdr_t);

  hdr->dofh_loadsz  = size;

  hdr->dofh_filesz  = size;

  // First section: STRTAB

  dof_sec_t* sec = (dof_sec_t*)(dof + sizeof(dof_hdr_t));

  sec->dofs_type    = DOF_SECT_STRTAB;

  sec->dofs_align   = alignment_for[STRTAB];

  sec->dofs_flags   = DOF_SECF_LOAD;

  sec->dofs_entsize = 0;

  sec->dofs_offset  = secoffs[STRTAB];

  sec->dofs_size    = secsize[STRTAB];

  // Make data for this section

  char* str = (char*)(dof + sec->dofs_offset);

  *str = 0; str += 1; // ""

  // Run through all strings again

  for(int prvc = 0; prvc < providers_count; ++prvc) {

    JVM_DTraceProvider* provider = &providers[prvc];

    char* provider_name = java_lang_String::as_utf8_string(

        JNIHandles::resolve_non_null(provider->name));

    strcpy(str, provider_name);

    str += strlen(provider_name) + 1;

    // All probes

    for(int prbc = 0; prbc < provider->probe_count; ++prbc) {

      JVM_DTraceProbe* p = &(provider->probes[prbc]);

      char* function = java_lang_String::as_utf8_string(

          JNIHandles::resolve_non_null(p->function));

      strcpy(str, function);

      str += strlen(str) + 1;

      char* name = java_lang_String::as_utf8_string(

          JNIHandles::resolve_non_null(p->name));

      strcpy(str, name);

      str += strlen(name) + 1;

      symbolOop sig = JNIHandles::resolve_jmethod_id(p->method)->signature();

      SignatureStream ss(sig);

      for ( ; !ss.at_return_type(); ss.next()) {

        BasicType bt = ss.type();

        const char* t;

        if (bt == T_OBJECT &&

            ss.as_symbol_or_null() == vmSymbols::java_lang_String()) {

          t = string_sig;

        } else if (bt == T_LONG) {

          t = long_sig;

        } else {

          t = int_sig;

        }

        strcpy(str, t);

        str += strlen(t) + 1;

      }

    }

  }

  curstr = 1;

  for(int prvc = 0; prvc < providers_count; ++prvc) {

    JVM_DTraceProvider* provider = &providers[prvc];

    size_t provider_sec  = PROVIDERS     + prvc * 4;

    size_t probe_sec     = PROBES        + prvc * 4;

    size_t probeoffs_sec = PROBE_OFFSETS + prvc * 4;

    size_t argoffs_sec   = ARG_OFFSETS   + prvc * 4;

    // PROVIDER ///////////////////////////////////////////////////////////////

    // Section header

    sec = (dof_sec_t*)

        (dof + sizeof(dof_hdr_t) + sizeof(dof_sec_t) * provider_sec);

    sec->dofs_type    = DOF_SECT_PROVIDER;

    sec->dofs_align   = alignment_for[PROVIDERS];

    sec->dofs_flags   = DOF_SECF_LOAD;

    sec->dofs_entsize = 0;

    sec->dofs_offset  = secoffs[provider_sec];

    sec->dofs_size    = secsize[provider_sec];

    // Make provider decriiption

    dof_provider_t* prv = (dof_provider_t*)(dof + sec->dofs_offset);

    prv->dofpv_strtab   = STRTAB;

    prv->dofpv_probes   = probe_sec;

    prv->dofpv_prargs   = argoffs_sec;

    prv->dofpv_proffs   = probeoffs_sec;

    prv->dofpv_name     = stroffs[curstr++]; // Index in string table

    prv->dofpv_provattr = DOF_ATTR(

        provider->providerAttributes.nameStability,

        provider->providerAttributes.dataStability,

        provider->providerAttributes.dependencyClass);

    prv->dofpv_modattr = DOF_ATTR(

        provider->moduleAttributes.nameStability,

        provider->moduleAttributes.dataStability,

        provider->moduleAttributes.dependencyClass);

    prv->dofpv_funcattr = DOF_ATTR(

        provider->functionAttributes.nameStability,

        provider->functionAttributes.dataStability,

        provider->functionAttributes.dependencyClass);

    prv->dofpv_nameattr = DOF_ATTR(

        provider->nameAttributes.nameStability,

        provider->nameAttributes.dataStability,

        provider->nameAttributes.dependencyClass);

    prv->dofpv_argsattr = DOF_ATTR(

        provider->argsAttributes.nameStability,

        provider->argsAttributes.dataStability,

        provider->argsAttributes.dependencyClass);

    // PROBES /////////////////////////////////////////////////////////////////

    // Section header

    sec = (dof_sec_t*)

        (dof + sizeof(dof_hdr_t) + sizeof(dof_sec_t) * probe_sec);

    sec->dofs_type    = DOF_SECT_PROBES;

    sec->dofs_align   = alignment_for[PROBES];

    sec->dofs_flags   = DOF_SECF_LOAD;

    sec->dofs_entsize = sizeof(dof_probe_t);

    sec->dofs_offset  = secoffs[probe_sec];

    sec->dofs_size    = secsize[probe_sec];

    // Make probes descriptions

    uint32_t argsoffs = 0;

    for(int prbc = 0; prbc < provider->probe_count; ++prbc) {

      JVM_DTraceProbe* probe = &(provider->probes[prbc]);

      methodOop m = JNIHandles::resolve_jmethod_id(probe->method);

      int arg_count = ArgumentCount(m->signature()).size();

      assert(m->code() != NULL, "must have an nmethod");

      dof_probe_t* prb =

         (dof_probe_t*)(dof + sec->dofs_offset + prbc * sizeof(dof_probe_t));

      prb->dofpr_addr   = (uint64_t)m->code()->entry_point();

      prb->dofpr_func   = stroffs[curstr++]; // Index in string table

      prb->dofpr_name   = stroffs[curstr++]; // Index in string table

      prb->dofpr_nargv  = stroffs[curstr  ]; // Index in string table

      // We spent siglen strings here

      curstr += arg_count;

      prb->dofpr_xargv  = prb->dofpr_nargv;  // Same bunch of strings

      prb->dofpr_argidx = argsoffs;

      prb->dofpr_offidx = prbc;

      prb->dofpr_nargc  = arg_count;

      prb->dofpr_xargc  = arg_count;

      prb->dofpr_noffs  = 1; // Number of offsets

      // Next bunch of offsets

      argsoffs += arg_count;

    }

    // PROFFS /////////////////////////////////////////////////////////////////

    // Section header

    sec = (dof_sec_t*)

        (dof + sizeof(dof_hdr_t) + sizeof(dof_sec_t) * probeoffs_sec);

    sec->dofs_type    = DOF_SECT_PROFFS;

    sec->dofs_align   = alignment_for[PROBE_OFFSETS];

    sec->dofs_flags   = DOF_SECF_LOAD;

    sec->dofs_entsize = sizeof(uint32_t);

    sec->dofs_offset  = secoffs[probeoffs_sec];

    sec->dofs_size    = secsize[probeoffs_sec];

    // Make offsets

    for (int prbc = 0; prbc < provider->probe_count; ++prbc) {

      uint32_t* pof =

          (uint32_t*)(dof + sec->dofs_offset + sizeof(uint32_t) * prbc);

      JVM_DTraceProbe* probe = &(provider->probes[prbc]);

      methodOop m = JNIHandles::resolve_jmethod_id(probe->method);

      *pof = m->code()->trap_offset();

    }

    // PRARGS /////////////////////////////////////////////////////////////////

    // Section header

    sec = (dof_sec_t*)

        (dof + sizeof(dof_hdr_t) + sizeof(dof_sec_t) * argoffs_sec);

    sec->dofs_type    = DOF_SECT_PRARGS;

    sec->dofs_align   = alignment_for[ARG_OFFSETS];

    sec->dofs_flags   = DOF_SECF_LOAD;

    sec->dofs_entsize = sizeof(uint8_t);

    sec->dofs_offset  = secoffs[argoffs_sec];

    sec->dofs_size    = secsize[argoffs_sec];

    // Make arguments

    uint8_t* par = (uint8_t*)(dof + sec->dofs_offset);

    for (int prbc = 0; prbc < provider->probe_count; ++prbc) {

      JVM_DTraceProbe* p = &(provider->probes[prbc]);

      symbolOop sig = JNIHandles::resolve_jmethod_id(p->method)->signature();

      uint8_t count = (uint8_t)ArgumentCount(sig).size();

      for (uint8_t i = 0; i < count; ++i) {

        *par++ = i;

      }

    }

  }

  // Register module

  return dof_register(module, dof, moduleBaseAddress);

}

void DTraceJSDT::pd_dispose(int handle) {

  int fd;

  if (handle == -1) {

    return;

  }

  fd = dofhelper_open();

  if (fd < 0)

    return;

  ioctl(fd, DTRACEHIOC_REMOVE, handle);

  close(fd);

}

jboolean DTraceJSDT::pd_is_supported() {

  int fd = dofhelper_open();

  if (fd < 0) {

    return false;

  }

  close(fd);

  return true;

}

static const char* dofSecTypeFor(uint32_t type) {

  switch (type) {

    case 0:  return "DOF_SECT_NONE";

    case 1:  return "DOF_SECT_COMMENTS";

    case 2:  return "DOF_SECT_SOURCE";

    case 3:  return "DOF_SECT_ECBDESC";

    case 4:  return "DOF_SECT_PROBEDESC";

    case 5:  return "DOF_SECT_ACTDESC";

    case 6:  return "DOF_SECT_DIFOHDR";

    case 7:  return "DOF_SECT_DIF";

    case 8:  return "DOF_SECT_STRTAB";

    case 9:  return "DOF_SECT_VARTAB";

    case 10: return "DOF_SECT_RELTAB";

    case 11: return "DOF_SECT_TYPETAB";

    case 12: return "DOF_SECT_URELHDR";

    case 13: return "DOF_SECT_KRELHDR";

    case 14: return "DOF_SECT_OPTDESC";

    case 15: return "DOF_SECT_PROVIDER";

    case 16: return "DOF_SECT_PROBES";

    case 17: return "DOF_SECT_PRARGS";

    case 18: return "DOF_SECT_PROFFS";

    case 19: return "DOF_SECT_INTTAB";

    case 20: return "DOF_SECT_UTSNAME";

    case 21: return "DOF_SECT_XLTAB";

    case 22: return "DOF_SECT_XLMEMBERS";

    case 23: return "DOF_SECT_XLIMPORT";

    case 24: return "DOF_SECT_XLEXPORT";

    case 25: return "DOF_SECT_PREXPORT";

    case 26: return "DOF_SECT_PRENOFFS";

    default: return "<unknown>";

  }

}

static void printDOFStringTabSec(void* dof, dof_sec_t* sec) {

  size_t tab = sec->dofs_offset;

  size_t limit = sec->dofs_size;

  tty->print_cr("//   String Table:");

  for (size_t idx = 0; idx < limit; /*empty*/) {

    char* str = ((char*)dof) + tab + idx;

    tty->print_cr("//   [0x%x + 0x%x] '%s'", tab, idx, str);

    idx += strlen(str) + 1;

  }

}

static void printDOFProviderSec(void* dof, dof_sec_t* sec) {

  dof_provider_t* prov = (dof_provider_t*)((char*)dof + sec->dofs_offset);

  tty->print_cr("//   dof_provider_t {");

  tty->print_cr("//     dofpv_strtab = %d", prov->dofpv_strtab);

  tty->print_cr("//     dofpv_probes = %d", prov->dofpv_probes);

  tty->print_cr("//     dofpv_prargs = %d", prov->dofpv_prargs);

  tty->print_cr("//     dofpv_proffs = %d", prov->dofpv_proffs);

  tty->print_cr("//     dofpv_name = 0x%x", prov->dofpv_name);

  tty->print_cr("//     dofpv_provattr = 0x%08x", prov->dofpv_provattr);

  tty->print_cr("//     dofpv_modattr = 0x%08x", prov->dofpv_modattr);

  tty->print_cr("//     dofpv_funcattr = 0x%08x", prov->dofpv_funcattr);

  tty->print_cr("//     dofpv_nameattr = 0x%08x", prov->dofpv_nameattr);

  tty->print_cr("//     dofpv_argsattr = 0x%08x", prov->dofpv_argsattr);

  tty->print_cr("//   }");