scc

simple c99 compiler
git clone git://git.simple-cc.org/scc
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commit c9423ef8b35ce37809c723e59b5921a3dc6df4e8
parent f3436a0f0eb428a516f9ccbf8b169ecfb3a676d5
Author: Roberto E. Vargas Caballero <k0ga@shike2.com>
Date:   Tue, 26 Feb 2019 11:22:25 +0000

[ld] Create a custom directory for ld

Ld is too complex to be only a file. It is better
to split it in a file per pass. We can always merge
them later.

Diffstat:
Minclude/scc/scc/mach.h | 5+++--
Msrc/cmd/Makefile | 7++-----
Dsrc/cmd/ld.c | 708-------------------------------------------------------------------------------
Asrc/cmd/ld/Makefile | 23+++++++++++++++++++++++
Asrc/cmd/ld/deps.mk | 14++++++++++++++
Asrc/cmd/ld/ld.h | 70++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Asrc/cmd/ld/main.c | 160+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Asrc/cmd/ld/pass1.c | 238+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Asrc/cmd/ld/pass2.c | 53+++++++++++++++++++++++++++++++++++++++++++++++++++++
Asrc/cmd/ld/pass3.c | 34++++++++++++++++++++++++++++++++++
Asrc/cmd/ld/symbol.c | 146+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Msrc/libmach/objread.c | 2++
12 files changed, 745 insertions(+), 715 deletions(-)

diff --git a/include/scc/scc/mach.h b/include/scc/scc/mach.h @@ -3,7 +3,7 @@ typedef struct objsect Objsect; typedef struct objsym Objsym; typedef struct objsymdef Objsymdef; -typedef struct object Obj; +typedef struct obj Obj; enum sectype { SREAD = 1 << 0, @@ -41,12 +41,13 @@ struct objsymdef { Objsymdef *hash, *next; }; -struct object { +struct obj { int type; char *index; Objsym *htab[NR_SYMHASH]; Objsym *syms;; Objsect *secs; + FILE *fp; fpos_t pos; int nsecs; int nsyms; diff --git a/src/cmd/Makefile b/src/cmd/Makefile @@ -13,7 +13,7 @@ TARGET = $(BINDIR)/nm \ $(BINDIR)/objcopy \ $(BINDIR)/addr2line \ -DIRS = as scc +DIRS = ld as scc LIBMACH = $(LIBDIR)/libmach.a LIBSCC = $(LIBDIR)/libscc.a @@ -21,7 +21,7 @@ LIBSCC = $(LIBDIR)/libscc.a all: $(TARGET) $(DIRS) $(DIRS): FORCE - @+cd $@ && $(MAKE) + +@cd $@ && $(MAKE) $(BINDIR)/nm: nm.o $(LIBMACH) $(LIBSCC) $(CC) $(SCC_LDFLAGS) nm.o -lmach -lscc -o $@ @@ -35,9 +35,6 @@ $(BINDIR)/size: size.o $(LIBMACH) $(LIBSCC) $(BINDIR)/ranlib: ranlib.o $(DRIVER).o $(LIBMACH) $(LIBSCC) $(CC) $(SCC_LDFLAGS) ranlib.o $(DRIVER).o -lmach -lscc -o $@ -$(BINDIR)/ld: ld.o $(LIBMACH) $(LIBSCC) - $(CC) $(SCC_LDFLAGS) ld.o -lmach -lscc -o $@ - $(BINDIR)/objdump: objdump.o $(LIBMACH) $(CC) $(SCC_LDFLAGS) objdump.o -lmach -o $@ diff --git a/src/cmd/ld.c b/src/cmd/ld.c @@ -1,708 +0,0 @@ -static char sccsid[] = "@(#) ./ld/main.c"; - -#include <ctype.h> -#include <errno.h> -#include <limits.h> -#include <stdarg.h> -#include <stdio.h> -#include <stdlib.h> -#include <string.h> - -#include <scc/mach.h> -#include <scc/scc.h> -#include <scc/ar.h> -#include <scc/syslibs.h> - -#define NR_SYMBOL 128 - -typedef struct objlst Objlst; -typedef struct symbol Symbol; -typedef struct section Section; - -enum { - NOINSTALL, - INSTALL, -}; - -enum { - OUTLIB, - INLIB, -}; - -struct section { - char *name; - unsigned long long size, offset; - unsigned flags; - int type; - FILE *fp; - Section *next; -}; - -struct objlst { - Obj *obj; - struct objlst *next; -}; - -struct symbol { - char *name; - Obj *obj; - Objsym *def; - unsigned long long size, value; - struct symbol *next, *prev; - struct symbol *hash; -}; - -char *output = "a.out", *entry = "start", *datasiz; - -static Section *sections; -static int bintype = -1; -static char *filename, *membname; -static Objlst *objhead, *objlast; -static Symbol *symtab[NR_SYMBOL]; -static Symbol refhead = { - .next = &refhead, - .prev = &refhead, -}; - -static int sflag; /* discard all the symbols */ -static int xflag; /* discard local symbols */ -static int Xflag; /* discard locals starting with 'L' */ -static int rflag; /* preserve relocation bits */ -static int dflag; /* define common even with rflag */ -static int gflag; /* preserve debug symbols */ - -static int status; - -static char * -errstr(void) -{ - return strerror(errno); -} - -static void -error(char *fmt, ...) -{ - va_list va; - - va_start(va, fmt); - fprintf(stderr, "ld: %s: ", filename); - if (membname) - fprintf(stderr, "%s: ", membname); - vfprintf(stderr, fmt, va); - putc('\n', stderr); - va_end(va); - - status = EXIT_FAILURE; -} - -static void -cleanup(void) -{ - if (status != EXIT_FAILURE) - remove(output); -} - -static int -moreundef(void) -{ - - return refhead.next != &refhead; -} - -static Symbol * -lookup(char *name, int install) -{ - size_t len; - char *s; - unsigned h; - Symbol *sym; - - h = genhash(name) % NR_SYMBOL; - - for (sym = symtab[h]; sym; sym = sym->hash) { - if (!strcmp(name, sym->name)) - return sym; - } - - if (!install) - return NULL; - - len = strlen(name) + 1; - sym = malloc(sizeof(*sym)); - s = malloc(len); - if (!len || !s) { - error("out of memory"); - exit(EXIT_FAILURE); - } - - sym->obj = NULL; - sym->name = memcpy(s, name, len); - sym->hash = symtab[h]; - symtab[h] = sym; - sym->value = 0; - sym->size = 0; - - refhead.next->prev = sym; - sym->next = refhead.next; - refhead.next = sym; - sym->prev = &refhead; - - return sym; -} - -static Symbol * -define(Objsym *osym, Obj *obj) -{ - Symbol *sym = lookup(osym->name, INSTALL); - - if (sym->def && sym->def->type != 'C') { - error("%s: symbol redefined", osym->name); - return NULL; - } - - sym->obj = obj; - sym->def = osym; - sym->size = osym->size; - sym->value = osym->value; - - sym->next->prev = sym->prev; - sym->prev->next = sym->next; - sym->next = sym->prev = NULL; - - return sym; -} - -static int -newsym(Objsym *osym, Obj *obj) -{ - Symbol *sym; - - switch (osym->type) { - case 'U': - lookup(osym->name, INSTALL); - case '?': - case 'N': - break; - case 'C': - sym = lookup(osym->name, NOINSTALL); - if (!sym || !sym->def) { - define(osym, obj); - break; - } - if (sym->def->type != 'C') - break; - if (sym->size < osym->size) - sym->size = osym->size; - break; - default: - if (isupper(osym->type)) - define(osym, obj); - break; - } - - return 1; -} - -static void -copy(FILE *to, FILE *from, long pad, long nbytes) -{ - int c; - - while (pad--) - putc(0, to); - - while (nbytes-- && (c = getc(from)) != EOF) - putc(c, to); - - if (c == EOF) { - error("section truncated"); - exit(EXIT_FAILURE); - } - - if (ferror(to) || ferror(from)) { - error(errstr()); - exit(EXIT_FAILURE); - } -} - -static Section * -findsect(Objsect *secp) -{ - size_t len; - char *s; - FILE *fp; - Section *sp, *lastp; - - for (lastp = sp = sections; sp; lastp = sp, sp = sp->next) { - if (!strcmp(sp->name, secp->name)) - return sp; - } - - len = strlen(secp->name) + 1; - s = malloc(len); - fp = tmpfile(); - - sp = malloc(sizeof(*sp)); - if (!s || !sp || !fp) { - error(errstr()); - exit(EXIT_FAILURE); - } - - if (lastp) { - lastp->next = sp; - } else { - sections = sp; - sp->next = NULL; - } - - sp->name = memcpy(s, secp->name, len); - sp->offset = sp->size = 0; - sp->fp = fp; - sp->flags = secp->flags; - sp->type = secp->type; - - return sp; -} - -extern int objpos(Obj *obj, FILE *fp, long pos); - -static void -newsect(Objsect *secp, Obj *obj, FILE *fp) -{ - unsigned long long align, size, pad, off; - Section *sp; - - sp = findsect(secp); - - align = secp->align - 1; - pad = (sp->size+align) & ~align; - - if (sp->size > ULLONG_MAX - pad) - goto overflow; - off = sp->size += pad; - - if (sp->size > ULLONG_MAX - secp->size) - goto overflow; - sp->size += secp->size; - - objpos(obj, fp, secp->offset); - copy(sp->fp, fp, pad, secp->size); - - /* - * and now update the offset to relect the offset - * in the output file - */ - secp->offset = off; - - return; - -overflow: - error("section overflow"); - exit(EXIT_FAILURE); -} - -static void -loadobj(Obj *obj, FILE *fp) -{ - int n; - Objlst *lst; - Objsym *sym; - Objsect *secp; - - if ((lst = malloc(sizeof(*lst))) == NULL) { - error("out of memory"); - return; - } - - lst->obj = obj; - lst->next = NULL; - - if (!objlast) - objlast = objhead = lst; - else - objlast = objlast->next = lst; - - for (sym = obj->syms; sym; sym = sym->next) - newsym(sym, obj); - - for (secp = obj->secs; secp; secp = secp->next) - newsect(secp, obj, fp); -} - -static void -newobject(FILE *fp, int type, int inlib) -{ - Obj *obj; - Symbol *sym, *p; - - if ((obj = objnew(type)) == NULL) { - error("out of memory"); - return; - } - - if (bintype == -1) { - bintype = type; - } else if (bintype != type) { - error("not compatible object file"); - goto delete; - } - bintype = type; - - if (objread(obj, fp) < 0) { - error("object file corrupted"); - goto delete; - } - - if (objsyms(obj) < 0 || objsect(obj) < 0) { - error("object file corrupted"); - goto delete; - } - - if (!inlib) { - loadobj(obj, fp); - return; - } - - /* - * we are in a library without index, so we have to check - * if it defines some symbol that is undefined and only - * in that case we have to load the object - */ - p = &refhead; - for (sym = p->next; sym != p; sym = sym->next) { - if (objlookup(obj, sym->name, 0)) { - loadobj(obj, fp); - return; - } - } - -delete: - objdel(obj); - return; -} - -static void -loadlib(FILE *fp) -{ - int t, loaded; - long n; - Objsymdef *def, *dp; - Symbol *sym; - - if (getindex(bintype, &n, &def, fp) < 0) { - error("corrupted index"); - return; - } - - loaded = 1; - while (moreundef() && loaded) { - loaded = 0; - for (dp = def; dp; dp = dp->next) { - sym = lookup(dp->name, NOINSTALL); - if (!sym || sym->def) - continue; - - if (fseek(fp, dp->offset, SEEK_SET) == EOF) { - error(errstr()); - goto clean; - } - - if ((t = objtype(fp, NULL)) == -1) { - error("library file corrupted"); - goto clean; - } - - if (t != bintype) { - error("incompatible library"); - goto clean; - } - - newobject(fp, t, OUTLIB); - loaded = 1; - } - } -clean: - free(def); -} - -static int -newmember(FILE *fp, char *name, void *data) -{ - int t; - int *nmemb = data; - - if (bintype == -1) { - error("an object file is needed before any library"); - return 0; - } - - if (*nmemb++ == 0) { - if (!strncmp(name, "/", SARNAM) || - !strncmp(name, "__.SYMDEF", SARNAM)) { - loadlib(fp); - return 0; - } - } - - membname = name; - if ((t = objtype(fp, NULL)) == -1) - return 1; - - if (bintype != t) { - error("wrong object file format"); - return 1; - } - - newobject(fp, t, INLIB); - membname = NULL; - - return 1; -} - -static int -newlibrary(FILE *fp) -{ - int nmemb = 0; - - return formember(fp, newmember, &nmemb); -} - -static FILE * -openfile(char *name, char *buffer) -{ - size_t pathlen, len; - FILE *fp; - char **bp, **base, **end; - char libname[FILENAME_MAX]; - - filename = name; - membname = NULL; - if (name[0] != '-' || name[1] != 'l') { - if ((fp = fopen(name, "rb")) == NULL) - error(errstr()); - return fp; - } - - len = strlen(name+2) + 3; - if (len > FILENAME_MAX-1) { - error("library name too long"); - return NULL; - } - strcat(strcpy(buffer, "lib"), name+2); - - filename = buffer; - if ((fp = fopen(libname, "rb")) != NULL) - return fp; - - base = syslibs; - end = &syslibs[MAX_LIB_PATHS]; - for (bp = base; bp < end && *bp; ++bp) { - pathlen = strlen(*bp); - if (pathlen + len > FILENAME_MAX-1) - continue; - memcpy(libname, *bp, pathlen); - memcpy(libname+pathlen+1, buffer, len); - buffer[pathlen] = '/'; - - if ((fp = fopen(buffer, "rb")) != NULL) - return fp; - } - - error("not found"); - return NULL; -} - -static void -listundef(void) -{ - Symbol *sym, *p; - - p = &refhead; - for (sym = p->next; sym != p; sym = sym->next) { - fprintf(stderr, - "ld: symbol '%s' not defined\n", - sym->name); - } -} - -static void -pass1(int argc, char *argv[]) -{ - int t; - FILE *fp; - char buff[FILENAME_MAX]; - - for ( ; *argv; ++argv) { - if ((fp = openfile(*argv, buff)) == NULL) - continue; - - if ((t = objtype(fp, NULL)) != -1) - newobject(fp, t, OUTLIB); - else if (archive(fp)) - newlibrary(fp); - else - error("bad format"); - - fclose(fp); - } - - if (moreundef()) { - listundef(); - exit(EXIT_FAILURE); - } -} - -/* - * default memory layout: - * -text - * -data - * -bss - */ -static void -pass2(int argc, char *argv[]) -{ - FILE *fp; - Section *sp; - long off; - unsigned long long addr; - - if ((fp = fopen("binary", "wb")) == NULL) { - perror("opening output"); - exit(EXIT_FAILURE); - } - - addr = 0x100; - for (sp = sections; sp; sp = sp->next) { - fprintf(stderr, "1st - %c\n", sp->type); - if (sp->type != 'T') - continue; - rewind(sp->fp); - copy(fp, sp->fp, 0, sp->size); - addr += sp->size; - fclose(sp->fp); - } - - addr = addr+3 & ~3; - for (sp = sections; sp; sp = sp->next) { - fprintf(stderr, "2nd - %c\n", sp->type); - if (sp->type != 'D') - continue; - rewind(sp->fp); - copy(fp, sp->fp, 0, sp->size); - addr += sp->size; - fclose(sp->fp); - } - - addr = addr+3 & ~3; - for (sp = sections; sp; sp = sp->next) { - fprintf(stderr, "3rd - %c\n", sp->type); - if (sp->type != 'B') - continue; - addr += sp->size; - fclose(sp->fp); - } -} - -static void -usage(void) -{ - fputs("usage: ld [options] file ...\n", stderr); - exit(EXIT_FAILURE); -} - -static void -Lpath(char *path) -{ - char **bp, **base, **end; - - base = syslibs; - end = &syslibs[MAX_LIB_PATHS]; - for (bp = base; bp < end && *bp; ++bp) - ; - if (bp == end) { - fputs("ld: too many -L options\n", stderr); - exit(1); - } - *bp = path; -} - -int -main(int argc, char *argv[]) -{ - char *cp, **p; - - for (--argc; *++argv; --argc) { - if (argv[0][0] != '-' || argv[0][1] == 'l') - break; - if (argv[0][1] == '-') { - --argc, ++argv; - break; - } - for (cp = &argv[0][1]; *cp; ++cp) { - switch (*cp) { - case 's': - sflag = 1; - break; - case 'x': - xflag = 1; - break; - case 'X': - Xflag = 1; - break; - case 'r': - rflag = 1; - break; - case 'd': - dflag = 1; - break; - case 'i': - case 'n': - /* TODO */ - break; - case 'L': - if (argc == 0) - goto usage; - ++argv, --argc; - Lpath(*argv); - break; - case 'u': - if (argc == 0) - goto usage; - ++argv, --argc; - lookup(*argv, INSTALL); - break; - case 'o': - if (argc == 0) - goto usage; - ++argv, --argc; - output = *argv; - break; - case 'e': - if (argc == 0) - goto usage; - ++argv, --argc; - entry = *argv; - break; - case 'D': - if (argc == 0) - goto usage; - ++argv, --argc; - datasiz = *argv; - break; - default: - usage: - usage(); - } - } - } - - if (argc == 0) - usage(); - - atexit(cleanup); - - pass1(argc, argv); - pass2(argc, argv); - - return status; -} diff --git a/src/cmd/ld/Makefile b/src/cmd/ld/Makefile @@ -0,0 +1,23 @@ +.POSIX: +PROJECTDIR = ../../.. +include $(PROJECTDIR)/scripts/rules.mk + +TARGET = $(BINDIR)/ld + +OBJS = main.o \ + symbol.o \ + pass1.o \ + pass2.o \ + pass3.o \ + + +all: $(TARGET) + +#TODO Add library dependencies +$(TARGET): $(OBJS) + $(CC) $(SCC_LDFLAGS) $(OBJS) -lmach -lscc -o $@ + +dep: inc-dep + +clean: + rm -f $(OBJS) diff --git a/src/cmd/ld/deps.mk b/src/cmd/ld/deps.mk @@ -0,0 +1,14 @@ +#deps +./main.o: $(INCDIR)/scc/scc/syslibs.h +./main.o: ./ld.h +./pass1.o: $(INCDIR)/scc/scc/ar.h +./pass1.o: $(INCDIR)/scc/scc/mach.h +./pass1.o: $(INCDIR)/scc/scc/scc.h +./pass1.o: ./ld.h +./pass2.o: $(INCDIR)/scc/scc/mach.h +./pass2.o: ./ld.h +./pass3.o: $(INCDIR)/scc/scc/mach.h +./pass3.o: ./ld.h +./symbol.o: $(INCDIR)/scc/scc/mach.h +./symbol.o: $(INCDIR)/scc/scc/scc.h +./symbol.o: ./ld.h diff --git a/src/cmd/ld/ld.h b/src/cmd/ld/ld.h @@ -0,0 +1,70 @@ +struct obj; +struct objsym; + +typedef struct objlst Objlst; +typedef struct symbol Symbol; +typedef struct section Section; + +enum { + NOINSTALL, + INSTALL, +}; + +enum { + OUTLIB, + INLIB, +}; + +struct section { + char *name; + unsigned long base; + unsigned long long size; + unsigned flags; + int type; + FILE *fp; + Section *next; +}; + +struct objlst { + struct obj *obj; + struct objlst *next; +}; + +struct symbol { + char *name; + struct obj *obj; + struct objsym *def; + unsigned long long size, value; + struct symbol *next, *prev; + struct symbol *hash; +}; + +/* passes */ +extern void pass1(int argc, char *argv[]); +extern void pass2(int argc, char *argv[]); +extern void pass3(int argc, char *argv[]); + +/* main.c */ +extern char *errstr(void); +extern void error(char *fmt, ...); + +/* symbol.c */ +extern Symbol *lookup(char *name, int install); +extern Symbol *define(struct objsym *osym, struct obj *obj); +extern int newsym(struct objsym *osym, struct obj *obj); +extern int moreundef(void); +extern void listundef(void); +extern int defasym(struct obj *obj); + +/* globals */ +extern char *filename, *membname; +extern unsigned long textsiz, datasiz, bsssiz; +extern unsigned long textbase, database, bssbase; +extern int sflag; +extern int xflag; +extern int Xflag; +extern int rflag; +extern int dflag; +extern int gflag; +extern char *Dflag; +extern Objlst *objhead, *objlast; diff --git a/src/cmd/ld/main.c b/src/cmd/ld/main.c @@ -0,0 +1,160 @@ +static char sccsid[] = "@(#) ./ld/main.c"; + +#include <errno.h> +#include <stdarg.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> + +#include <scc/syslibs.h> + +#include "ld.h" + +char *output = "a.out", *entry = "start"; + +char *filename, *membname; +unsigned long textsiz, datasiz, bsssiz; +unsigned long textbase, database, bssbase; + +int sflag; /* discard all the symbols */ +int xflag; /* discard local symbols */ +int Xflag; /* discard locals starting with 'L' */ +int rflag; /* preserve relocation bits */ +int dflag; /* define common even with rflag */ +int gflag; /* preserve debug symbols */ +char *Dflag; /* size of data */ + +static int status; + +char * +errstr(void) +{ + return strerror(errno); +} + +void +error(char *fmt, ...) +{ + va_list va; + + va_start(va, fmt); + fprintf(stderr, "ld: %s: ", filename); + if (membname) + fprintf(stderr, "%s: ", membname); + vfprintf(stderr, fmt, va); + putc('\n', stderr); + va_end(va); + + status = EXIT_FAILURE; +} + +static void +cleanup(void) +{ + if (status != EXIT_FAILURE) + remove(output); +} + +static void +usage(void) +{ + fputs("usage: ld [options] file ...\n", stderr); + exit(EXIT_FAILURE); +} + +static void +Lpath(char *path) +{ + char **bp, **end; + + end = &syslibs[MAX_LIB_PATHS]; + for (bp = syslibs; bp < end && *bp; ++bp) + ; + if (bp == end) { + fputs("ld: too many -L options\n", stderr); + exit(1); + } + *bp = path; +} + +int +main(int argc, char *argv[]) +{ + char *cp, **p; + + for (--argc; *++argv; --argc) { + if (argv[0][0] != '-' || argv[0][1] == 'l') + break; + if (argv[0][1] == '-') { + --argc, ++argv; + break; + } + for (cp = &argv[0][1]; *cp; ++cp) { + switch (*cp) { + case 's': + sflag = 1; + break; + case 'x': + xflag = 1; + break; + case 'X': + Xflag = 1; + break; + case 'r': + rflag = 1; + break; + case 'd': + dflag = 1; + break; + case 'i': + case 'n': + /* TODO */ + break; + case 'L': + if (argc == 0) + goto usage; + ++argv, --argc; + Lpath(*argv); + break; + case 'u': + if (argc == 0) + goto usage; + ++argv, --argc; + lookup(*argv, INSTALL); + break; + case 'o': + if (argc == 0) + goto usage; + ++argv, --argc; + output = *argv; + break; + case 'e': + if (argc == 0) + goto usage; + ++argv, --argc; + entry = *argv; + break; + case 'D': + if (argc == 0) + goto usage; + ++argv, --argc; + Dflag = *argv; + break; + default: + usage: + usage(); + } + } + } + + if (argc == 0) + usage(); + + atexit(cleanup); + + pass1(argc, argv); + pass2(argc, argv); + pass3(argc, argv); + + return status; +} diff --git a/src/cmd/ld/pass1.c b/src/cmd/ld/pass1.c @@ -0,0 +1,238 @@ +#include <stdarg.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> + +#include <scc/mach.h> +#include <scc/scc.h> +#include <scc/ar.h> + +#include "ld.h" + +static int bintype = -1; +Objlst *objhead, *objlast; + +static void +loadobj(Obj *obj, FILE *fp) +{ + int n; + Objlst *lst; + Objsym *sym; + Objsect *secp; + + if ((lst = malloc(sizeof(*lst))) == NULL) { + error("out of memory"); + return; + } + + lst->obj = obj; + lst->next = NULL; + + if (!objlast) + objlast = objhead = lst; + else + objlast = objlast->next = lst; + + for (sym = obj->syms; sym; sym = sym->next) + newsym(sym, obj); +} + +static void +newobject(FILE *fp, int type, int inlib) +{ + Obj *obj; + + if ((obj = objnew(type)) == NULL) { + error("out of memory"); + return; + } + + if (bintype != -1 && bintype != type) { + error("not compatible object file"); + goto delete; + } + bintype = type; + + if (objread(obj, fp) < 0) { + error("object file corrupted"); + goto delete; + } + + if (objsyms(obj) < 0 || objsect(obj) < 0) { + error("object file corrupted"); + goto delete; + } + + /* + * we add the object to the list of objects + * if we are not in a library without index, + * or in that case if the library defines + * some symbol needed. + */ + if (!inlib || defasym(obj)) { + loadobj(obj, fp); + return; + } + + delete: + objdel(obj); + return; +} + +static void +loadlib(FILE *fp) +{ + int t, loaded; + long n; + Objsymdef *def, *dp; + Symbol *sym; + + if (getindex(bintype, &n, &def, fp) < 0) { + error("corrupted index"); + return; + } + + loaded = 1; + while (moreundef() && loaded) { + loaded = 0; + for (dp = def; dp; dp = dp->next) { + sym = lookup(dp->name, NOINSTALL); + if (!sym || sym->def) + continue; + + if (fseek(fp, dp->offset, SEEK_SET) == EOF) { + error(errstr()); + goto clean; + } + + if ((t = objtype(fp, NULL)) == -1) { + error("library file corrupted"); + goto clean; + } + + if (t != bintype) { + error("incompatible library"); + goto clean; + } + + newobject(fp, t, OUTLIB); + loaded = 1; + } + } +clean: + free(def); +} + +static int +newmember(FILE *fp, char *name, void *data) +{ + int t; + int *nmemb = data; + + if (bintype == -1) { + error("an object file is needed before any library"); + return 0; + } + + if (*nmemb++ == 0) { + if (!strncmp(name, "/", SARNAM) || + !strncmp(name, "__.SYMDEF", SARNAM)) { + loadlib(fp); + return 0; + } + } + + membname = name; + if ((t = objtype(fp, NULL)) == -1) + return 1; + + if (bintype != t) { + error("wrong object file format"); + return 1; + } + + newobject(fp, t, INLIB); + membname = NULL; + + return 1; +} + +static int +newlibrary(FILE *fp) +{ + int nmemb = 0; + + return formember(fp, newmember, &nmemb); +} + +static FILE * +openfile(char *name, char *buffer) +{ + size_t pathlen, len; + FILE *fp; + char **bp; + char libname[FILENAME_MAX]; + extern char *syslibs[]; + + filename = name; + membname = NULL; + if (name[0] != '-' || name[1] != 'l') { + if ((fp = fopen(name, "rb")) == NULL) + error(errstr()); + return fp; + } + + len = strlen(name+2) + 3; + if (len > FILENAME_MAX-1) { + error("library name too long"); + return NULL; + } + strcat(strcpy(buffer, "lib"), name+2); + + filename = buffer; + if ((fp = fopen(libname, "rb")) != NULL) + return fp; + + for (bp = syslibs; *bp; ++bp) { + pathlen = strlen(*bp); + if (pathlen + len > FILENAME_MAX-1) + continue; + memcpy(libname, *bp, pathlen); + memcpy(libname+pathlen+1, buffer, len); + buffer[pathlen] = '/'; + + if ((fp = fopen(buffer, "rb")) != NULL) + return fp; + } + + error("not found"); + return NULL; +} + +/* + * Get the list of object files that are going to be linked + */ +void +pass1(int argc, char *argv[]) +{ + int t; + FILE *fp; + char buff[FILENAME_MAX]; + + for ( ; *argv; ++argv) { + if ((fp = openfile(*argv, buff)) == NULL) + continue; + + if ((t = objtype(fp, NULL)) != -1) + newobject(fp, t, OUTLIB); + else if (archive(fp)) + newlibrary(fp); + else + error("bad format"); + } + + if (moreundef()) { + listundef(); + exit(EXIT_FAILURE); + } +} diff --git a/src/cmd/ld/pass2.c b/src/cmd/ld/pass2.c @@ -0,0 +1,53 @@ +#include <stdlib.h> +#include <stdio.h> +#include <limits.h> + +#include <scc/mach.h> + +#include "ld.h" + +static unsigned long long +sectsize(int type) +{ + unsigned long long size; + Objlst *lp; + Objsect *sp; + + size = 0; + for (lp = objhead; lp; lp = lp->next) { + for (sp = lp->obj->secs; sp; sp = sp->next) { + if (sp->type != type) + continue; + size += sp->size; + } + } + + return size; +} + +/* + * calculate the size of every segment + */ +void +pass2(int argc, char *argv[]) +{ + unsigned long long n; + char *end; + Objsect *sp; + + datasiz = bsssiz = textsiz = 0; + + textsiz = sectsize('T'); + datasiz = sectsize('D'); + bsssiz = sectsize('B'); + + if (Dflag) { + n = strtoull(Dflag, &end, 0); + if (n == ULLONG_MAX || *end != '\0') { + error("incorrect -D value"); + exit(EXIT_FAILURE); + } + if (n > datasiz) + datasiz = n; + } +} diff --git a/src/cmd/ld/pass3.c b/src/cmd/ld/pass3.c @@ -0,0 +1,34 @@ +#include <stdio.h> +#include <stdlib.h> + +#include <scc/mach.h> + +#include "ld.h" + +/* + * relocate the sections + */ +void +pass3(int argc, char *argv[]) +{ + Obj *obj; + Objlst *lst; + Objsect *sp; + unsigned long long text, data, bss; + + textbase = text = 0; + database = data = textsiz+3 & ~3; + bssbase = bss = data+datasiz+3 & ~3; + + for (lst = objhead; lst; lst = lst->next) { + for (sp = lst->obj->secs; sp; sp = sp->next) { + switch (sp->type) { + case 'T': + case 'D': + case 'B': + default: + abort(); + } + } + } +} diff --git a/src/cmd/ld/symbol.c b/src/cmd/ld/symbol.c @@ -0,0 +1,146 @@ +#include <ctype.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> + +#include <scc/mach.h> +#include <scc/scc.h> + +#include "ld.h" + +#define NR_SYMBOL 128 + +static Symbol *symtab[NR_SYMBOL]; + +static Symbol refhead = { + .next = &refhead, + .prev = &refhead, +}; + +Symbol * +lookup(char *name, int install) +{ + size_t len; + char *s; + unsigned h; + Symbol *sym; + + h = genhash(name) % NR_SYMBOL; + + for (sym = symtab[h]; sym; sym = sym->hash) { + if (!strcmp(name, sym->name)) + return sym; + } + + if (!install) + return NULL; + + len = strlen(name) + 1; + sym = malloc(sizeof(*sym)); + s = malloc(len); + if (!len || !s) { + error("out of memory"); + exit(EXIT_FAILURE); + } + + sym->obj = NULL; + sym->name = memcpy(s, name, len); + sym->hash = symtab[h]; + symtab[h] = sym; + sym->value = 0; + sym->size = 0; + + refhead.next->prev = sym; + sym->next = refhead.next; + refhead.next = sym; + sym->prev = &refhead; + + return sym; +} + +Symbol * +define(Objsym *osym, Obj *obj) +{ + Symbol *sym = lookup(osym->name, INSTALL); + + if (sym->def && sym->def->type != 'C') { + error("%s: symbol redefined", osym->name); + return NULL; + } + + sym->obj = obj; + sym->def = osym; + sym->size = osym->size; + sym->value = osym->value; + + sym->next->prev = sym->prev; + sym->prev->next = sym->next; + sym->next = sym->prev = NULL; + + return sym; +} + +int +newsym(Objsym *osym, Obj *obj) +{ + Symbol *sym; + + switch (osym->type) { + case 'U': + lookup(osym->name, INSTALL); + case '?': + case 'N': + break; + case 'C': + sym = lookup(osym->name, NOINSTALL); + if (!sym || !sym->def) { + define(osym, obj); + break; + } + if (sym->def->type != 'C') + break; + if (sym->size < osym->size) + sym->size = osym->size; + break; + default: + if (isupper(osym->type)) + define(osym, obj); + break; + } + + return 1; +} + +int +moreundef(void) +{ + + return refhead.next != &refhead; +} + +void +listundef(void) +{ + Symbol *sym, *p; + + p = &refhead; + for (sym = p->next; sym != p; sym = sym->next) { + fprintf(stderr, + "ld: symbol '%s' not defined\n", + sym->name); + } +} + +int +defasym(Obj *obj) +{ + Symbol *sym, *p; + + p = &refhead; + for (sym = p->next; sym != p; sym = sym->next) { + if (objlookup(obj, sym->name, 0)) + return 1; + } + + return 0; +} diff --git a/src/libmach/objread.c b/src/libmach/objread.c @@ -19,5 +19,7 @@ objread(Obj *obj, FILE *fp) if ((*funv[fmt])(obj, fp) < 0) return -1; + obj->fp = fp; + return 0; }