Changed copy() to use a two pass algorithm: Now SYS first calls

copy to read kernel and command.com into RAM, then updates the
boot sector, then calls copy again to write kernel and command
from RAM to disk. This reduces disk changes a lot when you do
SYS A: B: on a PC which only has 1 diskette drive ("DJ style").


git-svn-id: https://svn.code.sf.net/p/freedos/svn/kernel/trunk@1349 6ac86273-5f31-0410-b378-82cca8765d1b

sys/sys.c

@@ -29,7 +29,7 @@
 #define DEBUG
 /* #define DDEBUG */
 
-#define SYS_VERSION "v3.2"
+#define SYS_VERSION "v3.3"
 
 #include <stdlib.h>
 #include <dos.h>
@@ -40,6 +40,7 @@
 #include <mem.h>
 #else
 #include <memory.h>
+#include <malloc.h> /* fmalloc() in open watcom */
 #endif
 #include <string.h>
 #ifdef __TURBOC__
@@ -161,7 +162,8 @@ BYTE pgm[] = "SYS";
 
 void put_boot(int, char *, char *, int, int);
 BOOL check_space(COUNT, ULONG);
-BOOL copy(COUNT drive, BYTE * srcPath, BYTE * rootPath, BYTE * file);
+BYTE far * copy(COUNT drive, BYTE * srcPath, BYTE * rootPath,
+  BYTE * file, BYTE far * buffer, ULONG * filesize);
 
 #define SEC_SIZE        512
 #define COPY_SIZE	0x7e00
@@ -240,12 +242,61 @@ struct VerifyBootSectorSize {
 
 int FDKrnConfigMain(int argc, char **argv);
 
+
+
+#ifndef __TURBOC__
+#ifdef __WATCOMC__
+
+/* int 21.48 takes a paragraph (16 byte units) count as input in bx */
+/* ... int 21.48 returns the segment after the allocated MCB in ax  */
+void far * farmalloc( ULONG __size );
+#pragma aux farmalloc = \
+      "shr cx, 1" \
+      "rcr bx, 1" \
+      "shr cx, 1" \
+      "rcr bx, 1" \
+      "shr cx, 1" \
+      "rcr bx, 1" \
+      "shr cx, 1" \
+      "rcr bx, 1" \
+      "inc bx" \
+      "xor dx, dx" \
+      "or cx, cx" \
+      "jnz nomalloc" \
+      "mov ax, 0x4800" \
+      "int 0x21" \
+      "jc nomalloc" \
+      "mov dx, ax" \
+"nomalloc:" \
+      "xor ax, ax" \
+      parm [cx bx] \
+      modify [bx] \
+      value [dx ax];
+
+void initalloc( void );
+#pragma aux initalloc = \
+      "push es" \
+      "mov ax, cs" \
+      "mov es, ax" \
+      "mov bx, 0x1000" \
+      "mov ax, 0x4a00" \
+      "int 0x21" \
+      "pop es" \
+      modify [ax bx];
+
+#endif
+#endif
+
 int main(int argc, char **argv)
 {
   COUNT drive;                  /* destination drive */
   COUNT drivearg = 0;           /* drive argument position */
   COUNT srcarg = 0;             /* source argument position */
   BYTE *bsFile = NULL;          /* user specified destination boot sector */
+  ULONG kernelsize = 0;		/* size of the kernel to be copied */
+  BYTE far *kernelbuf = NULL;	/* kernel to be copied */
+  ULONG shellsize = 0;		/* size of the shell to be copied */
+  BYTE far *shellbuf = NULL;	/* shell to be copied */
   unsigned srcDrive;            /* source drive */
   BYTE srcPath[SYS_MAXPATH];    /* user specified source drive and/or path */
   BYTE rootPath[4];             /* alternate source path to try if not '\0' */
@@ -256,6 +307,10 @@ int main(int argc, char **argv)
   char *kernel_name = "KERNEL.SYS";
   int load_segment = 0x60;
 
+#ifdef __WATCOMC__
+  initalloc(); /* reduce main MCB of .com file to 64 kB */
+#endif
+
   printf("FreeDOS System Installer " SYS_VERSION ", " __DATE__ "\n\n");
 
   if (argc > 1 && memicmp(argv[1], "CONFIG", 6) == 0)
@@ -368,35 +423,54 @@ int main(int argc, char **argv)
   else
     sprintf(rootPath, "%c:\\", 'A' + srcDrive);
 
-  printf("Processing boot sector...\n");
-  put_boot(drive, bsFile, kernel_name, load_segment, both);
-
   if (!bootonly)
   {
-    printf("\nCopying %s...\n", kernel_name);
+    printf("Reading %s...\n", kernel_name);
-    if (!copy(drive, srcPath, rootPath, kernel_name))
+    kernelbuf = copy(drive, srcPath, rootPath, kernel_name, NULL, &kernelsize);
+    if (kernelbuf == NULL)
     {
-      printf("\n%s: cannot copy \"%s\"\n", pgm, kernel_name);
+      printf("\n%s: cannot read \"%s\"\n", pgm, kernel_name);
       exit(1);
-    } /* copy kernel */
+    } /* fetch kernel */
-
+    printf("\nReading COMMAND.COM...\n");
-    printf("\nCopying COMMAND.COM...\n");
+    shellbuf = copy(drive, srcPath, rootPath, "COMMAND.COM", NULL, &shellsize);
-    if (!copy(drive, srcPath, rootPath, "COMMAND.COM"))
+    if (shellbuf == NULL)
     {
       char *comspec = getenv("COMSPEC");
       if (comspec != NULL)
       {
         printf("%s: Trying \"%s\"\n", pgm, comspec);
-        if (!copy(drive, comspec, NULL, "COMMAND.COM"))
+        shellbuf = copy(drive, comspec, NULL, "COMMAND.COM", NULL, &shellsize);
+        if (shellbuf == NULL)
           comspec = NULL;
       }
       if (comspec == NULL)
       {
-        printf("\n%s: cannot copy \"COMMAND.COM\"\n", pgm);
+        printf("\n%s: cannot read \"COMMAND.COM\"\n", pgm);
         exit(1);
       }
-    } /* copy shell */
+    } /* fetch shell */
-  }
+  } /* file READS */
+
+  printf("\nProcessing boot sector...\n"); /* READ and WRITE */
+  put_boot(drive, bsFile, kernel_name, load_segment, both);
+
+  if (!bootonly)
+  {
+    printf("\nWriting %s...\n", kernel_name);    
+    if (copy(drive, NULL, rootPath, kernel_name, kernelbuf, &kernelsize)==NULL)
+    {
+      printf("\n%s: cannot write \"%s\"\n", pgm, kernel_name);
+      exit(1);
+    } /* write kernel */
+
+    printf("\nWriting COMMAND.COM...\n");
+    if (copy(drive, NULL, rootPath, "COMMAND.COM", shellbuf, &shellsize)==NULL)
+    {
+      printf("\n%s: cannot write \"COMMAND.COM\"\n", pgm);
+      exit(1);
+    } /* write shell */
+  } /* file WRITES */
 
   printf("\nSystem transferred.\n");
   return 0;
@@ -932,19 +1006,30 @@ BOOL check_space(COUNT drive, ULONG bytes)
 
 BYTE copybuffer[COPY_SIZE];
 
-BOOL copy(COUNT drive, BYTE * srcPath, BYTE * rootPath, BYTE * file)
+/* if buffer is NULL, read the file, set filesize, and return a buffer */
+/* if buffer is not NULL, write, according to filesize, from buffer... */
+BYTE far * copy(COUNT drive, BYTE * srcPath, BYTE * rootPath,
+  BYTE * file, BYTE far * buffer, ULONG * filesize)
 {
   static BYTE dest[SYS_MAXPATH], source[SYS_MAXPATH];
-  unsigned ret;
+  UWORD ret;
   int fdin, fdout;
   ULONG copied = 0;
   struct stat fstatbuf;
+  BOOL reading = (buffer==NULL);
 
   strcpy(source, srcPath);
   if (rootPath != NULL) /* trick for comspec */
     strcat(source, file);
 
-  if (stat(source, &fstatbuf))
+  if (!reading && *filesize==0) /* write mode but no writing needed */
+  {
+     printf("%s: source and destination were identical: skipping \"%s\"\n",
+             pgm, source);
+     return buffer;
+  }
+
+  if (reading && stat(source, &fstatbuf)) /* read mode */
   {
     printf("%s: \"%s\" not found\n", pgm, source);
 
@@ -955,47 +1040,116 @@ BOOL copy(COUNT drive, BYTE * srcPath, BYTE * rootPath, BYTE * file)
       if (stat(source, &fstatbuf))
       {
         printf("%s: \"%s\" not found\n", pgm, source);
-        return FALSE;
+        return NULL;
       }
     }
     else
-      return FALSE;
+      return NULL;
   }
 
-  truename(dest, source);
+  if (reading) /* if reading */
-  strcpy(source, dest);
+  {
+    truename(dest, source);	/* use dest as buffer for truename(source) */
+    strcpy(source, dest);	/* write updated source string */
     sprintf(dest, "%c:\\%s", 'A' + drive, file);
     if (stricmp(source, dest) == 0)
     {
       printf("%s: source and destination are identical: skipping \"%s\"\n",
              pgm, source);
-    return TRUE;
+      *filesize = 0; /* special size */
+      return (BYTE far *) 1;	/* return something non-null */
     }
 
     if ((fdin = open(source, O_RDONLY | O_BINARY)) < 0)
     {
       printf("%s: failed to open \"%s\"\n", pgm, source);
-    return FALSE;
+      return NULL;
     }
+    *filesize = filelength(fdin); /* return size */
+  } /* reading */
 
-  if (!check_space(drive, filelength(fdin)))
+  if (!reading) /* writing */
+  {
+    if (!check_space(drive, *filesize))
     {
       printf("%s: Not enough space to transfer %s\n", pgm, file);
-    close(fdin);
+      /* close(fdin); */
-    exit(1);
+      /* exit(1); too pessimistic? we might overwrite a pre-existing file */
+      return NULL; /* still pessimistic, did not even try to overwrite... */
     }
 
+    sprintf(dest, "%c:\\%s", 'A' + drive, file);
     if ((fdout =
        open(dest, O_RDWR | O_TRUNC | O_CREAT | O_BINARY,
             S_IREAD | S_IWRITE)) < 0)
     {
       printf(" %s: can't create\"%s\"\nDOS errnum %d", pgm, dest, errno);
-    close(fdin);
+      /* close(fdin); */
-    return FALSE;
+      return NULL;
     }
+  } /* writing */
 
+  if (reading) /* reading */
+  {
+    BYTE far *bufptr;
+#ifdef __TURBOC__ /* workaround: farmalloc is nearmalloc if tiny model in TC2 ?? */
+    UWORD theseg;
+    if (allocmem((*filesize+15)>>4, &theseg)!=-1) /* allocate dos memory */
+#else
+    buffer = (BYTE far *)farmalloc(*filesize);
+    if (buffer==NULL)
+#endif
+    {
+      printf("Not enough memory to buffer %lu bytes for %s\n", *filesize, source);
+      return NULL;
+    }
+#ifdef __TURBOC__
+    buffer = MK_FP(theseg, 0);
+#endif
+    bufptr = buffer;
     while ((ret = read(fdin, copybuffer, COPY_SIZE)) > 0)
     {
+      UWORD offs;
+      if ((copied+ret) > *filesize)
+      {
+        ULONG dropped = copied + ret - *filesize;
+        printf("More bytes received than expected, dropping %lu??", dropped);
+        ret = ret - (UWORD) dropped;
+      }
+      for (offs = 0; offs < ret; offs++)
+      {
+        *bufptr = copybuffer[offs];
+        bufptr++;
+        if (FP_OFF(bufptr) > 0x7777) /* watcom needs this in tiny model */
+        {
+          bufptr = MK_FP(FP_SEG(bufptr)+0x700, FP_OFF(bufptr)-0x7000);
+        }
+      }
+      copied += ret;
+    }
+  } /* reading */
+
+  if (!reading) /* writing */
+  {
+    BYTE far * bufptr = buffer;
+    while (TRUE)
+    {
+      UWORD offs;      
+      ULONG tocopy = *filesize - copied;
+      if (tocopy==0)
+        break; /* done */
+      if (tocopy > (ULONG)COPY_SIZE)
+        tocopy = COPY_SIZE; /* cannot do all in one go */
+      for (offs=0; offs < tocopy; offs++)
+      {
+        copybuffer[offs] = *bufptr;
+        bufptr++;
+        if (FP_OFF(bufptr) > 0x7777) /* watcom needs this in tiny model */
+        {
+          bufptr = MK_FP(FP_SEG(bufptr)+0x700, FP_OFF(bufptr)-0x7000);
+        }
+      }
+      ret = (UWORD) tocopy;
       if (write(fdout, copybuffer, ret) != ret)
       {
         printf("Can't write %u bytes to %s\n", ret, dest);
@@ -1005,7 +1159,9 @@ BOOL copy(COUNT drive, BYTE * srcPath, BYTE * rootPath, BYTE * file)
       }
       copied += ret;
     }
+  } /* writing */
 
+#if 0 /* TODO: Clone file timestamps even in 2 pass copy mode... */
   {
 #if defined __WATCOMC__ || defined _MSC_VER /* || defined __BORLANDC__ */
     unsigned short date, time;	  
@@ -1017,10 +1173,14 @@ BOOL copy(COUNT drive, BYTE * srcPath, BYTE * rootPath, BYTE * file)
     setftime(fdout, &ftime);
 #endif
   }
+#endif /* timestamps */
 
+  if (reading)
     close(fdin);
+  if (!reading)
     close(fdout);
 
+#if 0 /* no way :-p */
 #ifdef __SOME_OTHER_COMPILER__
   {
 #include <utime.h>
@@ -1030,10 +1190,11 @@ BOOL copy(COUNT drive, BYTE * srcPath, BYTE * rootPath, BYTE * file)
         utimb.modtime = fstatbuf.st_mtime;      /* modification time */
     utime(dest, &utimb);
   };
+#endif
 #endif
 
   printf("%lu Bytes transferred", copied);
 
-  return TRUE;
+  return buffer;
 } /* copy */