Add preliminary support for truss on MIPS. It compiles, but has not

been extensively tested.  And the ELF64 stuff likely is not quite
right...

# There's a lot of cut-n-paste code here that could easily be
# refactored, at least for FreeBSD syscalls.

3 files changed, 354 insertions, 0 deletions

diff --git a/usr.bin/truss/extern.h b/usr.bin/truss/extern.h
index 69f23198c67d..fc3b0380f522 100644
--- a/usr.bin/truss/extern.h
+++ b/usr.bin/truss/extern.h
@@ -63,4 +63,8 @@ extern long powerpc_syscall_exit(struct trussinfo *, int);
 extern void sparc64_syscall_entry(struct trussinfo *, int);
 extern long sparc64_syscall_exit(struct trussinfo *, int);
 #endif
+#ifdef __mips__
+extern void mips_syscall_entry(struct trussinfo *, int);
+extern long mips_syscall_exit(struct trussinfo *, int);
+#endif
 
diff --git a/usr.bin/truss/main.c b/usr.bin/truss/main.c
index a735f34f27b3..54f7ee8c43e7 100644
--- a/usr.bin/truss/main.c
+++ b/usr.bin/truss/main.c
@@ -99,6 +99,11 @@ struct ex_types {
 #ifdef __sparc64__
 	{ "FreeBSD ELF64", sparc64_syscall_entry, sparc64_syscall_exit },
 #endif
+#ifdef __mips__
+	{ "FreeBSD ELF", mips_syscall_entry, mips_syscall_exit },
+	{ "FreeBSD ELF32", mips_syscall_entry, mips_syscall_exit },
+	{ "FreeBSD ELF64", mips_syscall_entry, mips_syscall_exit }, // XXX
+#endif
 	{ 0, 0, 0 },
 };
 
diff --git a/usr.bin/truss/mips-fbsd.c b/usr.bin/truss/mips-fbsd.c
new file mode 100644
index 000000000000..34137d8d89f7
--- /dev/null
+++ b/usr.bin/truss/mips-fbsd.c
@@ -0,0 +1,345 @@
+/*
+ * Copryight 1998 Sean Eric Fagan
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *	This product includes software developed by Sean Eric Fagan
+ * 4. Neither the name of the author may be used to endorse or promote
+ *    products derived from this software without specific prior written
+ *    permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#ifndef lint
+static const char rcsid[] =
+  "$FreeBSD$";
+#endif /* not lint */
+
+/*
+ * FreeBSD/sparc64-specific system call handling.  This is probably the most
+ * complex part of the entire truss program, although I've got lots of
+ * it handled relatively cleanly now.  The system call names are generated
+ * automatically, thanks to /usr/src/sys/kern/syscalls.master.  The
+ * names used for the various structures are confusing, I sadly admit.
+ *
+ * This file is almost nothing more than a slightly-edited i386-fbsd.c.
+ */
+
+#include <sys/types.h>
+#include <sys/ptrace.h>
+#include <sys/syscall.h>
+
+#include <machine/frame.h>
+#include <machine/reg.h>
+
+#include <err.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <signal.h>
+#include <stddef.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+#include <unistd.h>
+
+#include "truss.h"
+#include "syscall.h"
+#include "extern.h"
+
+static int cpid = -1;
+
+#include "syscalls.h"
+
+static int nsyscalls = sizeof(syscallnames) / sizeof(syscallnames[0]);
+
+/*
+ * This is what this particular file uses to keep track of a system call.
+ * It is probably not quite sufficient -- I can probably use the same
+ * structure for the various syscall personalities, and I also probably
+ * need to nest system calls (for signal handlers).
+ *
+ * 'struct syscall' describes the system call; it may be NULL, however,
+ * if we don't know about this particular system call yet.
+ */
+static struct freebsd_syscall {
+	struct syscall *sc;
+	const char *name;
+	int number;
+	unsigned long *args;
+	int nargs;	/* number of arguments -- *not* number of words! */
+	char **s_args;	/* the printable arguments */
+} fsc;
+
+/* Clear up and free parts of the fsc structure. */
+static __inline void
+clear_fsc(void) {
+  if (fsc.args) {
+    free(fsc.args);
+  }
+  if (fsc.s_args) {
+    int i;
+    for (i = 0; i < fsc.nargs; i++)
+      if (fsc.s_args[i])
+	free(fsc.s_args[i]);
+    free(fsc.s_args);
+  }
+  memset(&fsc, 0, sizeof(fsc));
+}
+
+/*
+ * Called when a process has entered a system call.  nargs is the
+ * number of words, not number of arguments (a necessary distinction
+ * in some cases).  Note that if the STOPEVENT() code in sparc64/sparc64/trap.c
+ * is ever changed these functions need to keep up.
+ */
+
+void
+mips_syscall_entry(struct trussinfo *trussinfo, int nargs) {
+  struct reg regs;
+  int syscall_num;
+  int i;
+  struct syscall *sc;
+  int indir = 0;	/* indirect system call */
+  struct ptrace_io_desc iorequest;
+
+  cpid = trussinfo->curthread->tid;
+
+  clear_fsc();
+  
+  if (ptrace(PT_GETREGS, cpid, (caddr_t)&regs, 0) < 0) {
+    fprintf(trussinfo->outfile, "-- CANNOT READ REGISTERS --\n");
+    return;
+  }
+
+  syscall_num = regs.r_regs[V0];
+  if (syscall_num == SYS_syscall) {
+    indir = 1;
+    syscall_num = regs.r_regs[A0];
+  }
+
+  fsc.number = syscall_num;
+  fsc.name =
+    (syscall_num < 0 || syscall_num > nsyscalls) ? NULL : syscallnames[syscall_num];
+  if (!fsc.name) {
+    fprintf(trussinfo->outfile, "-- UNKNOWN SYSCALL %d --\n", syscall_num);
+  }
+
+  if (fsc.name && (trussinfo->flags & FOLLOWFORKS)
+   && ((!strcmp(fsc.name, "fork")
+    || !strcmp(fsc.name, "rfork")
+    || !strcmp(fsc.name, "vfork"))))
+  {
+    trussinfo->curthread->in_fork = 1;
+  }
+
+  if (nargs == 0)
+    return;
+
+#if 0 // XXX
+  fsc.args = malloc((1+nargs) * sizeof(unsigned long));
+  iorequest.piod_op = PIOD_READ_D;
+  iorequest.piod_offs = (void *)parm_offset;
+  iorequest.piod_addr = fsc.args;
+  iorequest.piod_len = (1+nargs) * sizeof(unsigned long);
+  ptrace(PT_IO, cpid, (caddr_t)&iorequest, 0);
+  if (iorequest.piod_len == 0)
+    return;
+#else
+  iorequest.piod_op = PIOD_READ_D;
+#endif
+
+  switch (nargs) {
+  default:
+	/*
+	 * The OS doesn't seem to allow more than 10 words of
+	 * parameters (yay!).  So we shouldn't be here.
+	 */
+	warn("More than 10 words (%d) of arguments!\n", nargs);
+	break;
+  case 10: case 9: case 8: case 7: case 6: case 5:
+	/*
+	 * If there are 7-10 words of arguments, they are placed
+	 * on the stack, as is normal for other processors.
+	 * The fall-through for all of these is deliberate!!!
+	 */
+	  // XXX BAD constant used here
+	iorequest.piod_op = PIOD_READ_D;
+	iorequest.piod_offs = (void *)(regs.r_regs[SP] + 4 * sizeof(uint32_t));
+	iorequest.piod_addr = &fsc.args[4];
+	iorequest.piod_len = (nargs - 4) * sizeof(fsc.args[0]);
+	ptrace(PT_IO, cpid, (caddr_t)&iorequest, 0);
+	if (iorequest.piod_len == 0) return;
+  case 4:	fsc.args[3] = regs.r_regs[A3];
+  case 3:	fsc.args[2] = regs.r_regs[A2];
+  case 2:	fsc.args[1] = regs.r_regs[A1];
+  case 1:	fsc.args[0] = regs.r_regs[A0];
+  case 0:
+	break;
+  }
+  if (indir) {
+    memmove(&fsc.args[0], &fsc.args[1], (nargs-1) * sizeof(fsc.args[0]));
+  }
+
+  sc = get_syscall(fsc.name);
+  if (sc) {
+    fsc.nargs = sc->nargs;
+  } else {
+#if DEBUG
+    fprintf(trussinfo->outfile, "unknown syscall %s -- setting args to %d\n",
+	   fsc.name, nargs);
+#endif
+    fsc.nargs = nargs;
+  }
+
+  fsc.s_args = malloc((1+fsc.nargs) * sizeof(char*));
+  memset(fsc.s_args, 0, fsc.nargs * sizeof(char*));
+  fsc.sc = sc;
+
+  /*
+   * At this point, we set up the system call arguments.
+   * We ignore any OUT ones, however -- those are arguments that
+   * are set by the system call, and so are probably meaningless
+   * now.  This doesn't currently support arguments that are
+   * passed in *and* out, however.
+   */
+
+  if (fsc.name) {
+
+#if DEBUG
+    fprintf(stderr, "syscall %s(", fsc.name);
+#endif
+    for (i = 0; i < fsc.nargs; i++) {
+#if DEBUG
+      fprintf(stderr, "0x%x%s",
+	      sc
+	      ? fsc.args[sc->args[i].offset]
+	      : fsc.args[i],
+	      i < (fsc.nargs - 1) ? "," : "");
+#endif
+      if (sc && !(sc->args[i].type & OUT)) {
+	fsc.s_args[i] = print_arg(&sc->args[i], fsc.args, 0, trussinfo);
+      }
+    }
+#if DEBUG
+    fprintf(stderr, ")\n");
+#endif
+  }
+
+#if DEBUG
+  fprintf(trussinfo->outfile, "\n");
+#endif
+
+  if (fsc.name != NULL &&
+      (!strcmp(fsc.name, "execve") || !strcmp(fsc.name, "exit"))) {
+
+    /* XXX
+     * This could be done in a more general
+     * manner but it still wouldn't be very pretty.
+     */
+    if (!strcmp(fsc.name, "execve")) {
+        if ((trussinfo->flags & EXECVEARGS) == 0)
+          if (fsc.s_args[1]) {
+            free(fsc.s_args[1]);
+            fsc.s_args[1] = NULL;
+          }
+        if ((trussinfo->flags & EXECVEENVS) == 0)
+          if (fsc.s_args[2]) {
+            free(fsc.s_args[2]);
+            fsc.s_args[2] = NULL;
+          }
+    }
+  }
+
+  return;
+}
+
+/*
+ * And when the system call is done, we handle it here.
+ * Currently, no attempt is made to ensure that the system calls
+ * match -- this needs to be fixed (and is, in fact, why S_SCX includes
+ * the sytem call number instead of, say, an error status).
+ */
+
+long
+mips_syscall_exit(struct trussinfo *trussinfo, int syscall_num __unused) {
+  struct reg regs;
+  long retval;
+  int i;
+  int errorp;
+  struct syscall *sc;
+
+  if (fsc.name == NULL)
+	return (-1);
+  cpid = trussinfo->curthread->tid;
+
+  if (ptrace(PT_GETREGS, cpid, (caddr_t)&regs, 0) < 0) {
+    fprintf(trussinfo->outfile, "\n");
+    return (-1);
+  }
+  retval = regs.r_regs[V0];
+  errorp = !!regs.r_regs[A3];
+
+  /*
+   * This code, while simpler than the initial versions I used, could
+   * stand some significant cleaning.
+   */
+
+  sc = fsc.sc;
+  if (!sc) {
+    for (i = 0; i < fsc.nargs; i++)
+      asprintf(&fsc.s_args[i], "0x%lx", fsc.args[i]);
+  } else {
+    /*
+     * Here, we only look for arguments that have OUT masked in --
+     * otherwise, they were handled in the syscall_entry function.
+     */
+    for (i = 0; i < sc->nargs; i++) {
+      char *temp;
+      if (sc->args[i].type & OUT) {
+	/*
+	 * If an error occurred, than don't bothe getting the data;
+	 * it may not be valid.
+	 */
+	if (errorp)
+	  asprintf(&temp, "0x%lx", fsc.args[sc->args[i].offset]);
+	else
+	  temp = print_arg(&sc->args[i], fsc.args, retval, trussinfo);
+	fsc.s_args[i] = temp;
+      }
+    }
+  }
+
+  if (fsc.name != NULL &&
+      (!strcmp(fsc.name, "execve") || !strcmp(fsc.name, "exit"))) {
+	trussinfo->curthread->in_syscall = 1;
+  }
+  /*
+   * It would probably be a good idea to merge the error handling,
+   * but that complicates things considerably.
+   */
+
+  print_syscall_ret(trussinfo, fsc.name, fsc.nargs, fsc.s_args, errorp, retval);
+  clear_fsc();
+
+  return (retval);
+}