Import sources from 2011-03-30 iso image

1 files changed, 328 insertions, 0 deletions

diff --git a/sys/src/libmach/obj.c b/sys/src/libmach/obj.c
new file mode 100755
index 000000000..7615a408c
--- /dev/null
+++ b/sys/src/libmach/obj.c
@@ -0,0 +1,328 @@
+/*
+ * obj.c
+ * routines universal to all object files
+ */
+#include <u.h>
+#include <libc.h>
+#include <bio.h>
+#include <ar.h>
+#include <mach.h>
+#include "obj.h"
+
+#define islocal(t)	((t)=='a' || (t)=='p')
+
+enum
+{
+	NNAMES	= 50,
+	MAXIS	= 8,		/* max length to determine if a file is a .? file */
+	MAXOFF	= 0x7fffffff,	/* larger than any possible local offset */
+	NHASH	= 1024,		/* must be power of two */
+	HASHMUL	= 79L,
+};
+
+int	_is2(char*),		/* in [$OS].c */
+	_is5(char*),
+	_is6(char*),
+	_is7(char*),
+	_is8(char*),
+	_is9(char*),
+	_isk(char*),
+	_isq(char*),
+	_isv(char*),
+	_isu(char*),
+	_read2(Biobuf*, Prog*),
+	_read5(Biobuf*, Prog*),
+	_read6(Biobuf*, Prog*),
+	_read7(Biobuf*, Prog*),
+	_read8(Biobuf*, Prog*),
+	_read9(Biobuf*, Prog*),
+	_readk(Biobuf*, Prog*),
+	_readq(Biobuf*, Prog*),
+	_readv(Biobuf*, Prog*),
+	_readu(Biobuf*, Prog*);
+
+typedef struct Obj	Obj;
+typedef struct Symtab	Symtab;
+
+struct	Obj		/* functions to handle each intermediate (.$O) file */
+{
+	char	*name;				/* name of each $O file */
+	int	(*is)(char*);			/* test for each type of $O file */
+	int	(*read)(Biobuf*, Prog*);	/* read for each type of $O file*/
+};
+
+static Obj	obj[] =
+{			/* functions to identify and parse each type of obj */
+	[Obj68020]	"68020 .2",	_is2, _read2,
+	[ObjAmd64]	"amd64 .6",	_is6, _read6,
+	[ObjArm]	"arm .5",	_is5, _read5,
+	[ObjAlpha]	"alpha .7",	_is7, _read7,
+	[Obj386]	"386 .8",	_is8, _read8,
+	[ObjSparc]	"sparc .k",	_isk, _readk,
+	[ObjPower]	"power .q",	_isq, _readq,
+	[ObjMips]	"mips .v",	_isv, _readv,
+	[ObjSparc64]	"sparc64 .u",	_isu, _readu,
+	[ObjPower64]	"power64 .9",	_is9, _read9,
+	[Maxobjtype]	0, 0
+};
+
+struct	Symtab
+{
+	struct	Sym 	s;
+	struct	Symtab	*next;
+};
+
+static	Symtab *hash[NHASH];
+static	Sym	*names[NNAMES];	/* working set of active names */
+
+static	int	processprog(Prog*,int);	/* decode each symbol reference */
+static	void	objreset(void);
+static	void	objlookup(int, char *, int, uint);
+static	void 	objupdate(int, int);
+
+int
+objtype(Biobuf *bp, char **name)
+{
+	int i;
+	char buf[MAXIS];
+
+	if(Bread(bp, buf, MAXIS) < MAXIS)
+		return -1;
+	Bseek(bp, -MAXIS, 1);
+	for (i = 0; i < Maxobjtype; i++) {
+		if (obj[i].is && (*obj[i].is)(buf)) {
+			if (name)
+				*name = obj[i].name;
+			return i;
+		}
+	}
+	return -1;
+}
+
+int
+isar(Biobuf *bp)
+{
+	int n;
+	char magbuf[SARMAG];
+
+	n = Bread(bp, magbuf, SARMAG);
+	if(n == SARMAG && strncmp(magbuf, ARMAG, SARMAG) == 0)
+		return 1;
+	return 0;
+}
+
+/*
+ * determine what kind of object file this is and process it.
+ * return whether or not this was a recognized intermediate file.
+ */
+int
+readobj(Biobuf *bp, int objtype)
+{
+	Prog p;
+
+	if (objtype < 0 || objtype >= Maxobjtype || obj[objtype].is == 0)
+		return 1;
+	objreset();
+	while ((*obj[objtype].read)(bp, &p))
+		if (!processprog(&p, 1))
+			return 0;
+	return 1;
+}
+
+int
+readar(Biobuf *bp, int objtype, vlong end, int doautos)
+{
+	Prog p;
+
+	if (objtype < 0 || objtype >= Maxobjtype || obj[objtype].is == 0)
+		return 1;
+	objreset();
+	while ((*obj[objtype].read)(bp, &p) && Boffset(bp) < end)
+		if (!processprog(&p, doautos))
+			return 0;
+	return 1;
+}
+
+/*
+ *	decode a symbol reference or definition
+ */
+static	int
+processprog(Prog *p, int doautos)
+{
+	if(p->kind == aNone)
+		return 1;
+	if(p->sym < 0 || p->sym >= NNAMES)
+		return 0;
+	switch(p->kind)
+	{
+	case aName:
+		if (!doautos)
+		if(p->type != 'U' && p->type != 'b')
+			break;
+		objlookup(p->sym, p->id, p->type, p->sig);
+		break;
+	case aText:
+		objupdate(p->sym, 'T');
+		break;
+	case aData:
+		objupdate(p->sym, 'D');
+		break;
+	default:
+		break;
+	}
+	return 1;
+}
+
+/*
+ * find the entry for s in the symbol array.
+ * make a new entry if it is not already there.
+ */
+static void
+objlookup(int id, char *name, int type, uint sig)
+{
+	long h;
+	char *cp;
+	Sym *s;
+	Symtab *sp;
+
+	s = names[id];
+	if(s && strcmp(s->name, name) == 0) {
+		s->type = type;
+		s->sig = sig;
+		return;
+	}
+
+	h = *name;
+	for(cp = name+1; *cp; h += *cp++)
+		h *= HASHMUL;
+	if(h < 0)
+		h = ~h;
+	h &= (NHASH-1);
+	if (type == 'U' || type == 'b' || islocal(type)) {
+		for(sp = hash[h]; sp; sp = sp->next)
+			if(strcmp(sp->s.name, name) == 0) {
+				switch(sp->s.type) {
+				case 'T':
+				case 'D':
+				case 'U':
+					if (type == 'U') {
+						names[id] = &sp->s;
+						return;
+					}
+					break;
+				case 't':
+				case 'd':
+				case 'b':
+					if (type == 'b') {
+						names[id] = &sp->s;
+						return;
+					}
+					break;
+				case 'a':
+				case 'p':
+					if (islocal(type)) {
+						names[id] = &sp->s;
+						return;
+					}
+					break;
+				default:
+					break;
+				}
+			}
+	}
+	sp = malloc(sizeof(Symtab));
+	sp->s.name = name;
+	sp->s.type = type;
+	sp->s.sig = sig;
+	sp->s.value = islocal(type) ? MAXOFF : 0;
+	names[id] = &sp->s;
+	sp->next = hash[h];
+	hash[h] = sp;
+	return;
+}
+/*
+ *	traverse the symbol lists
+ */
+void
+objtraverse(void (*fn)(Sym*, void*), void *pointer)
+{
+	int i;
+	Symtab *s;
+
+	for(i = 0; i < NHASH; i++)
+		for(s = hash[i]; s; s = s->next)
+			(*fn)(&s->s, pointer);
+}
+
+/*
+ * update the offset information for a 'a' or 'p' symbol in an intermediate file
+ */
+void
+_offset(int id, vlong off)
+{
+	Sym *s;
+
+	s = names[id];
+	if (s && s->name[0] && islocal(s->type) && s->value > off)
+		s->value = off;
+}
+
+/*
+ * update the type of a global text or data symbol
+ */
+static void 
+objupdate(int id, int type)
+{
+	Sym *s;
+
+	s = names[id];
+	if (s && s->name[0])
+		if (s->type == 'U')
+			s->type = type;
+		else if (s->type == 'b')
+			s->type = tolower(type);
+}
+
+/*
+ * look for the next file in an archive
+ */
+int
+nextar(Biobuf *bp, int offset, char *buf)
+{
+	struct ar_hdr a;
+	int i, r;
+	long arsize;
+
+	if (offset&01)
+		offset++;
+	Bseek(bp, offset, 0);
+	r = Bread(bp, &a, SAR_HDR);
+	if(r != SAR_HDR)
+		return 0;
+	if(strncmp(a.fmag, ARFMAG, sizeof(a.fmag)))
+		return -1;
+	for(i=0; i<sizeof(a.name) && i<SARNAME && a.name[i] != ' '; i++)
+		buf[i] = a.name[i];
+	buf[i] = 0;
+	arsize = strtol(a.size, 0, 0);
+	if (arsize&1)
+		arsize++;
+	return arsize + SAR_HDR;
+}
+
+static void
+objreset(void)
+{
+	int i;
+	Symtab *s, *n;
+
+	for(i = 0; i < NHASH; i++) {
+		for(s = hash[i]; s; s = n) {
+			n = s->next;
+			free(s->s.name);
+			free(s);
+		}
+		hash[i] = 0;
+	}
+	memset(names, 0, sizeof names);
+}