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Rewrites ATARI EXE segment writing to optimally write segment sizes.

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We now expand segments as needed to write a minimal set of headers.
This commit is contained in:
Daniel Serpell 2018-09-27 00:06:52 -03:00
parent 4e51fcbdd4
commit 2aa5b4cafe
1 changed files with 89 additions and 14 deletions
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103
src/ld65/xex.c
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@ -65,6 +65,9 @@ struct XexDesc {
FILE* F; /* Output file */
const char* Filename; /* Name of output file */
Import* RunAd; /* Run Address */
unsigned long HeadPos; /* Position in the file of current header */
unsigned long HeadEnd; /* End address of current header */
unsigned long HeadSize; /* Last header size, can be removed if zero */
};
@ -86,6 +89,9 @@ XexDesc* NewXexDesc (void)
D->F = 0;
D->Filename = 0;
D->RunAd = 0;
D->HeadPos = 0;
D->HeadEnd = 0;
D->HeadSize = 0;
/* Return the created struct */
return D;
@ -130,25 +136,80 @@ static void PrintNumVal (const char* Name, unsigned long V)
static void XexStartSegment (XexDesc *D, unsigned long Addr, unsigned long Size)
{
/* Skip segment without size */
if (!Size)
return;
/* Store current position */
unsigned long Pos = ftell (D->F);
unsigned long End = Addr + Size - 1;
/* See if last header can be expanded into this one */
if (D->HeadPos && ((D->HeadEnd + 1) == Addr)) {
/* Expand current header */
D->HeadEnd = End;
D->HeadSize += Size;
fseek (D->F, D->HeadPos + 2, SEEK_SET);
Write16 (D->F, End);
/* Seek to old position */
fseek (D->F, Pos, SEEK_SET);
}
else
{
if (D->HeadSize == 0) {
/* Last header had no data, replace */
Pos = D->HeadPos;
fseek (D->F, Pos, SEEK_SET);
}
/* If we are at start of file, write XEX heder */
if (Pos == 0)
Write16 (D->F, 0xFFFF);
/* Writes a new segment header */
D->HeadPos = ftell (D->F);
D->HeadEnd = End;
D->HeadSize = Size;
Write16 (D->F, Addr);
Write16 (D->F, End);
}
}
static void XexFakeSegment (XexDesc *D, unsigned long Addr)
{
/* See if last header can be expanded into this one, we are done */
if (D->HeadPos && ((D->HeadEnd + 1) == Addr))
return;
/* If we are at start of file, write XEX heder */
if (ftell (D->F) == 0)
Write16 (D->F, 0xFFFF);
/* Writes a new (invalid) segment header */
D->HeadPos = ftell (D->F);
D->HeadEnd = Addr - 1;
D->HeadSize = 0;
Write16 (D->F, Addr);
Write16 (D->F, D->HeadEnd);
}
static void XexWriteMem (XexDesc* D, MemoryArea* M)
/* Write the segments of one memory area to a file */
{
unsigned I;
/* Always write a segment header for each memory area */
D->HeadPos = 0;
/* Get the start address and size of this memory area */
unsigned long Addr = M->Start;
/* Real size of the memory area, either the FillLevel or the Size */
unsigned long Size = M->FillLevel;
if ((M->Flags & MF_FILL) != 0 && M->FillLevel < M->Size)
Size = M->Size;
/* Write header */
if (ftell (D->F) == 0)
Write16(D->F, 0xFFFF);
Write16(D->F, Addr);
Write16(D->F, Addr + Size - 1);
/* Walk over all segments in this memory area */
for (I = 0; I < CollCount (&M->SegList); ++I) {
@ -158,7 +219,7 @@ static void XexWriteMem (XexDesc* D, MemoryArea* M)
SegDesc* S = CollAtUnchecked (&M->SegList, I);
/* Keep the user happy */
Print (stdout, 1, " Allocating `%s'\n", GetString (S->Name));
Print (stdout, 1, " ATARI EXE Writing `%s'\n", GetString (S->Name));
/* Writes do only occur in the load area and not for BSS segments */
DoWrite = (S->Flags & SF_BSS) == 0 && /* No BSS segment */
@ -178,6 +239,7 @@ static void XexWriteMem (XexDesc* D, MemoryArea* M)
/* Align the address */
unsigned long NewAddr = AlignAddr (Addr, S->RunAlignment);
if (DoWrite || (M->Flags & MF_FILL) != 0) {
XexStartSegment (D, Addr, NewAddr - Addr);
WriteMult (D->F, M->FillVal, NewAddr - Addr);
PrintNumVal ("SF_ALIGN", NewAddr - Addr);
}
@ -194,6 +256,7 @@ static void XexWriteMem (XexDesc* D, MemoryArea* M)
Error ("ATARI file format does not support overwrite for segment '%s'.",
GetString (S->Name));
} else {
XexStartSegment (D, Addr, NewAddr - Addr);
WriteMult (D->F, M->FillVal, NewAddr-Addr);
PrintNumVal ("SF_OFFSET", NewAddr - Addr);
}
@ -208,6 +271,7 @@ static void XexWriteMem (XexDesc* D, MemoryArea* M)
/* Align the address */
unsigned long NewAddr = AlignAddr (Addr, S->LoadAlignment);
if (DoWrite || (M->Flags & MF_FILL) != 0) {
XexStartSegment (D, Addr, NewAddr - Addr);
WriteMult (D->F, M->FillVal, NewAddr - Addr);
PrintNumVal ("SF_ALIGN_LOAD", NewAddr - Addr);
}
@ -220,10 +284,16 @@ static void XexWriteMem (XexDesc* D, MemoryArea* M)
** if the memory area is the load area.
*/
if (DoWrite) {
/* Start a segment with only one byte, will fix later */
XexFakeSegment (D, Addr);
unsigned long P = ftell (D->F);
SegWrite (D->Filename, D->F, S->Seg, XexWriteExpr, D);
PrintNumVal ("Wrote", (unsigned long) (ftell (D->F) - P));
unsigned long Size = ftell (D->F) - P;
/* Fix segment size */
XexStartSegment (D, Addr, Size);
PrintNumVal ("Wrote", Size);
} else if (M->Flags & MF_FILL) {
XexStartSegment (D, Addr, S->Seg->Size);
WriteMult (D->F, S->Seg->FillVal, S->Seg->Size);
PrintNumVal ("Filled", (unsigned long) S->Seg->Size);
}
@ -242,10 +312,15 @@ static void XexWriteMem (XexDesc* D, MemoryArea* M)
unsigned long ToFill = M->Size - M->FillLevel;
Print (stdout, 2, " Filling 0x%lx bytes with 0x%02x\n",
ToFill, M->FillVal);
XexStartSegment (D, Addr, ToFill);
WriteMult (D->F, M->FillVal, ToFill);
M->FillLevel = M->Size;
}
/* If the last segment is empty, remove */
if (D->HeadSize == 0 && D->HeadPos) {
fseek (D->F, D->HeadPos, SEEK_SET);
}
}
@ -294,7 +369,7 @@ void XexWriteTarget (XexDesc* D, struct File* F)
for (I = 0; I < CollCount (&F->MemoryAreas); ++I) {
/* Get this entry */
MemoryArea* M = CollAtUnchecked (&F->MemoryAreas, I);
Print (stdout, 1, " XEX Dumping `%s'\n", GetString (M->Name));
Print (stdout, 1, " ATARI EXE Dumping `%s'\n", GetString (M->Name));
XexWriteMem (D, M);
}