ld: remove cseekend and redo pe writing

Simplify code and add more checks.

Fixes #2105.

R=rsc
CC=golang-dev
https://golang.org/cl/4794060

diff --git a/src/cmd/ld/lib.c b/src/cmd/ld/lib.c
index 86ed8476aa3d0c839e6f4b8311f4673ce7e981c3..5d1e6d61b47e89ccf3ec6761aee50b28c40f6162 100644 (file)
--- a/src/cmd/ld/lib.c
+++ b/src/cmd/ld/lib.c
@@ -1415,9 +1415,3 @@ cwrite(void *buf, int n)
        }
        coutpos += n;
 }
-
-void
-cseekend(void)
-{
-       seek(cout, 0, 2);
-}

diff --git a/src/cmd/ld/lib.h b/src/cmd/ld/lib.h
index e226f0122cdcd40079d220f14c79b1e995c7b2e0..0764dc7a7931478ea38632526a09f23ba9c7e457 100644 (file)
--- a/src/cmd/ld/lib.h
+++ b/src/cmd/ld/lib.h
@@ -302,7 +302,6 @@ EXTERN      char*   cbpmax;
 void   cflush(void);
 vlong  cpos(void);
 void   cseek(vlong);
-void   cseekend(void);
 void   cwrite(void*, int);
 void   importcycles(void);
 int    Zconv(Fmt*);

diff --git a/src/cmd/ld/pe.c b/src/cmd/ld/pe.c
index d235e33c1311d46515abaf045aaedff6bad72aff..6608a97dce42ce905d05126a005e6f93d1f60365 100644 (file)
--- a/src/cmd/ld/pe.c
+++ b/src/cmd/ld/pe.c
@@ -76,7 +76,7 @@ static Sym *dexport[1024];
 static int nexport;
 
 static IMAGE_SECTION_HEADER*
-addpesection(char *name, int sectsize, int filesize, Segment *s)
+addpesection(char *name, int sectsize, int filesize)
 {
        IMAGE_SECTION_HEADER *h;
 
@@ -94,19 +94,31 @@ addpesection(char *name, int sectsize, int filesize, Segment *s)
                h->SizeOfRawData = rnd(filesize, PEFILEALIGN);
                nextfileoff += h->SizeOfRawData;
        }
-       if(s) {
-               if(s->vaddr-PEBASE != h->VirtualAddress) {
-                       diag("%s.VirtualAddress = %#llux, want %#llux", name, (vlong)h->VirtualAddress, (vlong)(s->vaddr-PEBASE));
-                       errorexit();
-               }
-               if(s->fileoff != h->PointerToRawData) {
-                       diag("%s.PointerToRawData = %#llux, want %#llux", name, (vlong)h->PointerToRawData, (vlong)(s->fileoff));
-                       errorexit();
-               }
-       }
        return h;
 }
 
+static void
+chksectoff(IMAGE_SECTION_HEADER *h, vlong off)
+{
+       if(off != h->PointerToRawData) {
+               diag("%s.PointerToRawData = %#llux, want %#llux", h->Name, (vlong)h->PointerToRawData, off);
+               errorexit();
+       }
+}
+
+static void
+chksectseg(IMAGE_SECTION_HEADER *h, Segment *s)
+{
+       if(s->vaddr-PEBASE != h->VirtualAddress) {
+               diag("%s.VirtualAddress = %#llux, want %#llux", h->Name, (vlong)h->VirtualAddress, (vlong)(s->vaddr-PEBASE));
+               errorexit();
+       }
+       if(s->fileoff != h->PointerToRawData) {
+               diag("%s.PointerToRawData = %#llux, want %#llux", h->Name, (vlong)h->PointerToRawData, (vlong)(s->fileoff));
+               errorexit();
+       }
+}
+
 void
 peinit(void)
 {
@@ -138,7 +150,6 @@ pewrite(void)
        cseek(0);
        cwrite(dosstub, sizeof dosstub);
        strnput("PE", 4);
-       cflush();
        // TODO: This code should not assume that the
        // memory representation is little-endian or
        // that the structs are packed identically to
@@ -213,39 +224,41 @@ initdynimport(void)
 }
 
 static void
-addimports(vlong fileoff, IMAGE_SECTION_HEADER *datsect)
+addimports(IMAGE_SECTION_HEADER *datsect)
 {
        IMAGE_SECTION_HEADER *isect;
        uvlong n, oftbase, ftbase;
+       vlong startoff, endoff;
        Imp *m;
        Dll *d;
        Sym* dynamic;
        
+       startoff = cpos();
        dynamic = lookup(".windynamic", 0);
 
        // skip import descriptor table (will write it later)
        n = 0;
        for(d = dr; d != nil; d = d->next)
                n++;
-       cseek(fileoff + sizeof(IMAGE_IMPORT_DESCRIPTOR) * (n + 1));
+       cseek(startoff + sizeof(IMAGE_IMPORT_DESCRIPTOR) * (n + 1));
 
        // write dll names
        for(d = dr; d != nil; d = d->next) {
-               d->nameoff = cpos() - fileoff;
+               d->nameoff = cpos() - startoff;
                strput(d->name);
        }
 
        // write function names
        for(d = dr; d != nil; d = d->next) {
                for(m = d->ms; m != nil; m = m->next) {
-                       m->off = nextsectoff + cpos() - fileoff;
+                       m->off = nextsectoff + cpos() - startoff;
                        wputl(0); // hint
                        strput(m->s->dynimpname);
                }
        }
        
        // write OriginalFirstThunks
-       oftbase = cpos() - fileoff;
+       oftbase = cpos() - startoff;
        n = cpos();
        for(d = dr; d != nil; d = d->next) {
                d->thunkoff = cpos() - n;
@@ -255,12 +268,13 @@ addimports(vlong fileoff, IMAGE_SECTION_HEADER *datsect)
        }
 
        // add pe section and pad it at the end
-       n = cpos() - fileoff;
-       isect = addpesection(".idata", n, n, 0);
+       n = cpos() - startoff;
+       isect = addpesection(".idata", n, n);
        isect->Characteristics = IMAGE_SCN_CNT_INITIALIZED_DATA|
                IMAGE_SCN_MEM_READ|IMAGE_SCN_MEM_WRITE;
+       chksectoff(isect, startoff);
        strnput("", isect->SizeOfRawData - n);
-       cflush();
+       endoff = cpos();
 
        // write FirstThunks (allocated in .data section)
        ftbase = dynamic->value - datsect->VirtualAddress - PEBASE;
@@ -270,10 +284,9 @@ addimports(vlong fileoff, IMAGE_SECTION_HEADER *datsect)
                        put(m->off);
                put(0);
        }
-       cflush();
        
        // finally write import descriptor table
-       cseek(fileoff);
+       cseek(startoff);
        for(d = dr; d != nil; d = d->next) {
                lputl(isect->VirtualAddress + oftbase + d->thunkoff);
                lputl(0);
@@ -286,7 +299,6 @@ addimports(vlong fileoff, IMAGE_SECTION_HEADER *datsect)
        lputl(0);
        lputl(0);
        lputl(0);
-       cflush();
        
        // update data directory
        dd[IMAGE_DIRECTORY_ENTRY_IMPORT].VirtualAddress = isect->VirtualAddress;
@@ -294,7 +306,7 @@ addimports(vlong fileoff, IMAGE_SECTION_HEADER *datsect)
        dd[IMAGE_DIRECTORY_ENTRY_IAT].VirtualAddress = dynamic->value - PEBASE;
        dd[IMAGE_DIRECTORY_ENTRY_IAT].Size = dynamic->size;
 
-       cseekend();
+       cseek(endoff);
 }
 
 static int
@@ -329,7 +341,7 @@ initdynexport(void)
 }
 
 void
-addexports(vlong fileoff)
+addexports(void)
 {
        IMAGE_SECTION_HEADER *sect;
        IMAGE_EXPORT_DIRECTORY e;
@@ -342,13 +354,13 @@ addexports(vlong fileoff)
        if (nexport == 0)
                return;
                
-       sect = addpesection(".edata", size, size, 0);
+       sect = addpesection(".edata", size, size);
        sect->Characteristics = IMAGE_SCN_CNT_INITIALIZED_DATA|IMAGE_SCN_MEM_READ;
+       chksectoff(sect, cpos());
        va = sect->VirtualAddress;
        dd[IMAGE_DIRECTORY_ENTRY_EXPORT].VirtualAddress = va;
        dd[IMAGE_DIRECTORY_ENTRY_EXPORT].Size = sect->VirtualSize;
 
-       cseek(fileoff);
        va_name = va + sizeof e + nexport*4;
        va_addr = va + sizeof e;
        va_na = va + sizeof e + nexport*8;
@@ -383,9 +395,6 @@ addexports(vlong fileoff)
        for(i=0; i<nexport; i++)
                strnput(dexport[i]->dynimpname, strlen(dexport[i]->dynimpname)+1);
        strnput("", sect->SizeOfRawData - size);
-       cflush();
-
-       cseekend();
 }
 
 void
@@ -428,7 +437,7 @@ newPEDWARFSection(char *name, vlong size)
        nextsymoff += strlen(name);
        symnames[nextsymoff] = 0;
        nextsymoff ++;
-       h = addpesection(s, size, size, 0);
+       h = addpesection(s, size, size);
        h->Characteristics = IMAGE_SCN_MEM_READ|
                IMAGE_SCN_MEM_DISCARDABLE;
 
@@ -445,9 +454,10 @@ addsymtable(void)
                return;
        
        size  = nextsymoff + 4;
-       h = addpesection(".symtab", size, size, 0);
+       h = addpesection(".symtab", size, size);
        h->Characteristics = IMAGE_SCN_MEM_READ|
                IMAGE_SCN_MEM_DISCARDABLE;
+       chksectoff(h, cpos());
        fh.PointerToSymbolTable = cpos();
        fh.NumberOfSymbols = 0;
        // put symbol string table
@@ -455,7 +465,6 @@ addsymtable(void)
        for (i=0; i<nextsymoff; i++)
                cput(symnames[i]);
        strnput("", h->SizeOfRawData - size);
-       cflush();
 }
 
 void
@@ -478,9 +487,10 @@ addpersrc(void)
        if(rsrcsym == nil)
                return;
        
-       h = addpesection(".rsrc", rsrcsym->size, rsrcsym->size, 0);
+       h = addpesection(".rsrc", rsrcsym->size, rsrcsym->size);
        h->Characteristics = IMAGE_SCN_MEM_READ|
                IMAGE_SCN_MEM_WRITE | IMAGE_SCN_CNT_INITIALIZED_DATA;
+       chksectoff(h, cpos());
        // relocation
        for(r=rsrcsym->r; r<rsrcsym->r+rsrcsym->nr; r++) {
                p = rsrcsym->p + r->off;
@@ -493,7 +503,6 @@ addpersrc(void)
        }
        cwrite(rsrcsym->p, rsrcsym->size);
        strnput("", h->SizeOfRawData - rsrcsym->size);
-       cflush();
 
        // update data directory
        dd[IMAGE_DIRECTORY_ENTRY_RESOURCE].VirtualAddress = h->VirtualAddress;
@@ -517,24 +526,24 @@ asmbpe(void)
                break;
        }
 
-       t = addpesection(".text", segtext.len, segtext.len, &segtext);
+       t = addpesection(".text", segtext.len, segtext.len);
        t->Characteristics = IMAGE_SCN_CNT_CODE|
                IMAGE_SCN_CNT_INITIALIZED_DATA|
                IMAGE_SCN_MEM_EXECUTE|IMAGE_SCN_MEM_READ;
+       chksectseg(t, &segtext);
 
-       d = addpesection(".data", segdata.len, segdata.filelen, &segdata);
+       d = addpesection(".data", segdata.len, segdata.filelen);
        d->Characteristics = IMAGE_SCN_CNT_INITIALIZED_DATA|
                IMAGE_SCN_MEM_READ|IMAGE_SCN_MEM_WRITE;
+       chksectseg(d, &segdata);
 
        if(!debug['s'])
                dwarfaddpeheaders();
 
-       addimports(nextfileoff, d);
-       
-       addexports(nextfileoff);
-       
+       cseek(nextfileoff);
+       addimports(d);
+       addexports();
        addsymtable();
-       
        addpersrc();
        
        fh.NumberOfSections = nsect;