1 files changed, 318 insertions, 0 deletions
diff --git a/src/libmach/DragonFly.c b/src/libmach/DragonFly.c
new file mode 100644
index 00000000..92ffdb92
--- /dev/null
+++ b/src/libmach/DragonFly.c
@@ -0,0 +1,318 @@
+/*
+ * process interface for DragonFly BSD
+ *
+ * we could be a little more careful about not using
+ * ptrace unless absolutely necessary.  this would let us
+ * look at processes without stopping them.
+ *
+ * I'd like to make this a bit more generic (there's too much
+ * duplication with Linux and presumably other systems),
+ * but ptrace is too damn system-specific.
+ */
+
+#include <u.h>
+#include <sys/ptrace.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <machine/reg.h>
+#include <signal.h>
+#include <errno.h>
+#include <libc.h>
+#include <mach.h>
+#include "ureg386.h"
+
+Mach *machcpu = &mach386;
+
+typedef struct PtraceRegs PtraceRegs;
+struct PtraceRegs
+{
+	Regs r;
+	int pid;
+};
+
+static int ptracerw(Map*, Seg*, ulong, void*, uint, int);
+static int ptraceregrw(Regs*, char*, ulong*, int);
+
+void
+unmapproc(Map *map)
+{
+	int i;
+
+	if(map == nil)
+		return;
+	for(i=0; i<map->nseg; i++)
+		while(i<map->nseg && map->seg[i].pid){
+			map->nseg--;
+			memmove(&map->seg[i], &map->seg[i+1], 
+				(map->nseg-i)*sizeof(map->seg[0]));
+		}
+}
+
+int
+mapproc(int pid, Map *map, Regs **rp)
+{
+	Seg s;
+	PtraceRegs *r;
+
+	if(ptrace(PT_ATTACH, pid, 0, 0) < 0)
+	if(ptrace(PT_READ_I, pid, 0, 0)<0 && errno!=EINVAL)
+	if(ptrace(PT_ATTACH, pid, 0, 0) < 0){
+		werrstr("ptrace attach %d: %r", pid);
+		return -1;
+	}
+
+	if(ctlproc(pid, "waitanyway") < 0){
+		ptrace(PT_DETACH, pid, 0, 0);
+		return -1;
+	}
+
+	memset(&s, 0, sizeof s);
+	s.base = 0;
+	s.size = 0xFFFFFFFF;
+	s.offset = 0;
+	s.name = "data";
+	s.file = nil;
+	s.rw = ptracerw;
+	s.pid = pid;
+	if(addseg(map, s) < 0)
+		return -1;
+
+	if((r = mallocz(sizeof(PtraceRegs), 1)) == nil)
+		return -1;
+	r->r.rw = ptraceregrw;
+	r->pid = pid;
+	*rp = (Regs*)r;
+	return 0;
+}
+
+int
+detachproc(int pid)
+{
+	return ptrace(PT_DETACH, pid, 0, 0);
+}
+
+static int
+ptracerw(Map *map, Seg *seg, ulong addr, void *v, uint n, int isr)
+{
+	int i;
+	u32int u;
+	uchar buf[4];
+
+	addr += seg->base;
+	for(i=0; i<n; i+=4){
+		if(isr){
+			errno = 0;
+			u = ptrace(PT_READ_D, seg->pid, (char*)addr+i, 0);
+			if(errno)
+				goto ptraceerr;
+			if(n-i >= 4)
+				*(u32int*)((char*)v+i) = u;
+			else{
+				*(u32int*)buf = u;
+				memmove((char*)v+i, buf, n-i);
+			}
+		}else{
+			if(n-i >= 4)
+				u = *(u32int*)((char*)v+i);
+			else{
+				errno = 0;
+				u = ptrace(PT_READ_D, seg->pid, (char*)addr+i, 0);
+				if(errno)
+					return -1;
+				*(u32int*)buf = u;
+				memmove(buf, (char*)v+i, n-i);
+				u = *(u32int*)buf;
+			}
+			if(ptrace(PT_WRITE_D, seg->pid, (char*)addr+i, u) < 0)
+				goto ptraceerr;
+		}
+	}
+	return 0;
+
+ptraceerr:
+	werrstr("ptrace: %r");
+	return -1;
+}
+
+static char *freebsdregs[] = {
+	"FS",
+	"ES",
+	"DS",
+	"DI",
+	"SI",
+	"BP",
+	"SP",
+	"BX",
+	"DX",
+	"CX",
+	"AX",
+	"TRAP",
+	"PC",
+	"CS",
+	"EFLAGS",
+	"SP",
+	"SS",
+	"GS",
+};
+
+static ulong
+reg2freebsd(char *reg)
+{
+	int i;
+
+	for(i=0; i<nelem(freebsdregs); i++)
+		if(strcmp(freebsdregs[i], reg) == 0)
+			return 4*i;
+	return ~(ulong)0;
+}
+
+static int
+ptraceregrw(Regs *regs, char *name, ulong *val, int isr)
+{
+	int pid;
+	ulong addr;
+	struct reg mregs;
+
+	addr = reg2freebsd(name);
+	if(~addr == 0){
+		if(isr){
+			*val = ~(ulong)0;
+			return 0;
+		}
+		werrstr("register not available");
+		return -1;
+	}
+
+	pid = ((PtraceRegs*)regs)->pid;
+	if(ptrace(PT_GETREGS, pid, (char*)&mregs, 0) < 0)
+		return -1;
+	if(isr)
+		*val = *(u32int*)((char*)&mregs+addr);
+	else{
+		*(u32int*)((char*)&mregs+addr) = *val;
+		if(ptrace(PT_SETREGS, pid, (char*)&mregs, 0) < 0)
+			return -1;
+	}
+	return 0;
+}
+
+char*
+proctextfile(int pid)
+{
+	static char buf[1024], pbuf[128];
+
+	snprint(pbuf, sizeof pbuf, "/proc/%d/file", pid);
+	if(readlink(pbuf, buf, sizeof buf) >= 0)
+		return buf;
+	if(access(pbuf, AEXIST) >= 0)
+		return pbuf;
+	return nil;
+}
+
+/*
+
+  status  The process status.  This file is read-only and returns a single
+	     line containing multiple space-separated fields as follows:
+
+	     o	 command name
+	     o	 process id
+	     o	 parent process id
+	     o	 process group id
+	     o	 session id
+	     o	 major,minor of the controlling terminal, or -1,-1 if there is
+		 no controlling terminal.
+	     o	 a list of process flags: ctty if there is a controlling ter-
+		 minal, sldr if the process is a session leader, noflags if
+		 neither of the other two flags are set.
+	     o	 the process start time in seconds and microseconds, comma
+		 separated.
+	     o	 the user time in seconds and microseconds, comma separated.
+	     o	 the system time in seconds and microseconds, comma separated.
+	     o	 the wait channel message
+	     o	 the process credentials consisting of the effective user id
+		 and the list of groups (whose first member is the effective
+		 group id) all comma separated.
+*/
+
+int
+procnotes(int pid, char ***pnotes)
+{
+	/* figure out the set of pending notes - how? */
+	*pnotes = nil;
+	return 0;
+}
+
+static int
+isstopped(int pid)
+{
+	char buf[1024], *f[12];
+	int fd, n, nf;
+
+	snprint(buf, sizeof buf, "/proc/%d/status", pid);
+	if((fd = open(buf, OREAD)) < 0)
+		return 0;
+	n = read(fd, buf, sizeof buf-1);
+	close(fd);
+	if(n <= 0)
+		return 0;
+	buf[n] = 0;
+
+	if((nf = tokenize(buf, f, nelem(f))) < 11)
+		return 0;
+	if(strcmp(f[10], "nochan") == 0)
+		return 1;
+	return 0;
+}
+
+#undef waitpid
+
+int
+ctlproc(int pid, char *msg)
+{
+	int p, status;
+
+	if(strcmp(msg, "hang") == 0){
+		if(pid == getpid())
+			return ptrace(PT_TRACE_ME, 0, 0, 0);
+		werrstr("can only hang self");
+		return -1;
+	}
+	if(strcmp(msg, "kill") == 0)
+		return ptrace(PT_KILL, pid, 0, 0);
+	if(strcmp(msg, "startstop") == 0){
+		if(ptrace(PT_CONTINUE, pid, 0, 0) < 0)
+			return -1;
+		goto waitstop;
+	}
+/*
+	if(strcmp(msg, "sysstop") == 0){
+		if(ptrace(PTRACE_SYSCALL, pid, 0, 0) < 0)
+			return -1;
+		goto waitstop;
+	}
+*/
+	if(strcmp(msg, "stop") == 0){
+		if(kill(pid, SIGSTOP) < 0)
+			return -1;
+		goto waitstop;
+	}
+	if(strcmp(msg, "waitanyway") == 0)
+		goto waitanyway;
+	if(strcmp(msg, "waitstop") == 0){
+	waitstop:
+		if(isstopped(pid))
+			return 0;
+	waitanyway:
+		for(;;){
+			p = waitpid(pid, &status, WUNTRACED);
+			if(p <= 0)
+				return -1;
+			if(WIFEXITED(status) || WIFSTOPPED(status))
+				return 0;
+		}
+	}
+	if(strcmp(msg, "start") == 0)
+		return ptrace(PT_CONTINUE, pid, 0, 0);
+	werrstr("unknown control message '%s'", msg);
+	return -1;
+}