WebSVN – SvarDOS – Diff – /svarcom/trunk/rmodinit.c


/* This file is part of the SvarCOM project and is published under the terms
 * of the MIT license.
 *
 * Copyright (C) 2021 Mateusz Viste
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
 * DEALINGS IN THE SOFTWARE.
 */
 
#include <i86.h>
#include <string.h>
 
#include "env.h"
#include "helpers.h"
 
#include "rmod.h"
 
#include "rmodinit.h"
 
 
/* returns far pointer to rmod's settings block on success */
struct rmod_props far *rmod_install(unsigned short envsize) {
  char far *myptr, far *mcb;
  unsigned short far *owner;
  const unsigned short sizeof_rmodandprops_paras = (0x100 + rmod_len + sizeof(struct rmod_props) + 15) / 16;
  unsigned short rmodseg = 0xffff;
  unsigned short envseg, origenvseg;
  struct rmod_props far *res = NULL;
 
  /* read my current env segment from PSP and save it */
  envseg = *((unsigned short *)0x2c);
  origenvseg = envseg;
 
  /* printf("original (PSP) env buffer at %04X\r\n", envseg); */
 
  /* if envseg is zero, then enforce our own one (MSDOS 5 does not provide a default env) */
  if ((envseg == 0) && (envsize == 0)) envsize = 256;
 
  /* if custom envsize requested, convert it to number of paragraphs */
  if (envsize != 0) {
    envsize += 15;
    envsize /= 16;
  }
 
  _asm {
    /* link in the UMB memory chain for enabling high-memory allocation (and save initial status on stack) */
    mov ax, 0x5802  /* GET UMB LINK STATE */
    int 0x21
    xor ah, ah
    push ax         /* save link state on stack */
    mov ax, 0x5803  /* SET UMB LINK STATE */
    mov bx, 1
    int 0x21
    /* get current allocation strategy and save it in DX */
    mov ax, 0x5800
    int 0x21
    push ax
    pop dx
    /* set strategy to 'last fit, try high then low memory' */
    mov ax, 0x5801
    mov bx, 0x0082
    int 0x21
    /* ask for a memory block and save the given segment to rmodseg */
    mov ah, 0x48
    mov bx, sizeof_rmodandprops_paras
    int 0x21
    jc ALLOC_FAIL
    mov rmodseg, ax
    /* ask for a memory block for the environment and save it to envseg (only if custom size requested) */
    mov bx, envsize
    test bx, bx
    jz ALLOC_FAIL
    mov ah, 0x48
    int 0x21
    jc ALLOC_FAIL
    mov envseg, ax
 
    ALLOC_FAIL:
    /* restore initial allocation strategy */
    mov ax, 0x5801
    mov bx, dx
    int 0x21
    /* restore initial UMB memory link state */
    mov ax, 0x5803
    pop bx       /* pop initial UMB link state from stack */
    int 0x21
  }
 
  if (rmodseg == 0xffff) {
    outputnl("malloc error");
    return(NULL);
  }
 
  /* copy rmod to its destination, prefixed with a copy of my own PSP */
  myptr = MK_FP(rmodseg, 0);
  {
    unsigned short i;
    char *mypsp = (void *)0;
    for (i = 0; i < 0x100; i++) myptr[i] = mypsp[i];
  }
  myptr = MK_FP(rmodseg, 0x100);
  _fmemcpy(myptr, rmod, rmod_len);
 
  /* mark rmod memory as "self owned" */
  mcb = MK_FP(rmodseg - 1, 0);
  owner = (void far *)(mcb + 1);
  *owner = rmodseg;
  _fmemcpy(mcb + 8, "SVARCOM", 8);
 
  /* mark env memory as "owned by rmod" */
  mcb = MK_FP(envseg - 1, 0);
  owner = (void far *)(mcb + 1);
  *owner = rmodseg;
  _fmemcpy(mcb + 8, "SVARENV", 8);
 
  /* if env block is newly allocated, fill it with a few NULLs */
  if (envsize != 0) {
    owner = MK_FP(envseg, 0);
    owner[0] = 0;
    owner[1] = 0;
  }
 
  /* prepare result (rmod props) */
  res = MK_FP(rmodseg, 0x100 + rmod_len);
  _fmemset(res, 0, sizeof(*res));  /* zero out */
  res->rmodseg = rmodseg;          /* rmod segment */
  res->inputbuf[0] = 128;          /* input buffer for INT 0x21, AH=0Ah*/
  res->echoflag = 1;               /* ECHO ON */
  res->origenvseg = origenvseg;    /* original environment segment */
 
  /* write env segment to rmod's PSP */
  owner = MK_FP(rmodseg, RMOD_OFFSET_ENVSEG);
  *owner = envseg;
 
  /* write boot drive to rmod bootdrive field */
  _asm {
    push ax
    push bx
    push dx
    push ds
    mov ax, 0x3305 /* DOS 4.0+ - GET BOOT DRIVE */
    int 0x21 /* boot drive is in DL now (1=A:, 2=B:, etc) */
    add dl, 'A'-1 /* convert to a proper ASCII letter */
    /* set DS to rmodseg */
    mov ax, rmodseg
    mov ds, ax
    /* write boot drive to rmod bootdrive field */
    mov bx, RMOD_OFFSET_BOOTDRIVE
    mov [bx], dl
    pop ds
    pop dx
    pop bx
    pop ax
  }
 
  /* save my original parent in rmod's memory */
  res->origparent = *((unsigned long *)0x0a); /* original parent seg:off is at 0x0a of my PSP */
 
  /* set the int22 handler in my PSP to rmod so DOS jumps to rmod after I
   * terminate and save the original handler in rmod's memory */
  {
    unsigned short *ptr = (void *)0x0a; /* int22 handler is at 0x0A of the PSP */
    ptr[0] = RMOD_OFFSET_ROUTINE;
    ptr[1] = rmodseg;
  }
 
  return(res);
}
 
 
/* look up my parent: if it's rmod then return a ptr to its props struct,
 * otherwise return NULL */
struct rmod_props far *rmod_find(void) {
  unsigned short *parent = (void *)0x0C; /* parent's seg in PSP[Ch] ("prev. int22 handler") */
  unsigned short far *ptr;
  const unsigned short sig[] = {0x1983, 0x1985, 0x2017, 0x2019};
  unsigned char i;
  /* is it rmod? */
  ptr = MK_FP(*parent, 0x100);
  for (i = 0; i < 4; i++) if (ptr[i] != sig[i]) return(NULL);
  /* match successfull (rmod is my parent) */
  return(MK_FP(*parent, 0x100 + rmod_len));
}
 
 
/* update rmod's pointer to comspec */
void rmod_updatecomspecptr(unsigned short rmod_seg, unsigned short env_seg) {
  unsigned short far *comspecptr = MK_FP(rmod_seg, RMOD_OFFSET_COMSPECPTR);
  char far *comspecfp = env_lookup_val(env_seg, "COMSPEC");
  if (comspecfp != NULL) {
    *comspecptr = FP_OFF(comspecfp);
  } else {
    *comspecptr = 0;
  }
}
 

Rev 454	Rev 459
1	`/* This file is part of the SvarCOM project and is published under the terms`	1	`/* This file is part of the SvarCOM project and is published under the terms`
2	`* of the MIT license.`	2	`* of the MIT license.`
3	`*`	3	`*`
4	`* Copyright (C) 2021 Mateusz Viste`	4	`* Copyright (C) 2021 Mateusz Viste`
5	`*`	5	`*`
6	`* Permission is hereby granted, free of charge, to any person obtaining a`	6	`* Permission is hereby granted, free of charge, to any person obtaining a`
7	`* copy of this software and associated documentation files (the "Software"),`	7	`* copy of this software and associated documentation files (the "Software"),`
8	`* to deal in the Software without restriction, including without limitation`	8	`* to deal in the Software without restriction, including without limitation`
9	`* the rights to use, copy, modify, merge, publish, distribute, sublicense,`	9	`* the rights to use, copy, modify, merge, publish, distribute, sublicense,`
10	`* and/or sell copies of the Software, and to permit persons to whom the`	10	`* and/or sell copies of the Software, and to permit persons to whom the`
11	`* Software is furnished to do so, subject to the following conditions:`	11	`* Software is furnished to do so, subject to the following conditions:`
12	`*`	12	`*`
13	`* The above copyright notice and this permission notice shall be included in`	13	`* The above copyright notice and this permission notice shall be included in`
14	`* all copies or substantial portions of the Software.`	14	`* all copies or substantial portions of the Software.`
15	`*`	15	`*`
16	`* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR`	16	`* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR`
17	`* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,`	17	`* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,`
18	`* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE`	18	`* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE`
19	`* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER`	19	`* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER`
20	`* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING`	20	`* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING`
21	`* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER`	21	`* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER`
22	`* DEALINGS IN THE SOFTWARE.`	22	`* DEALINGS IN THE SOFTWARE.`
23	`*/`	23	`*/`
24		24
25	`#include <i86.h>`	25	`#include <i86.h>`
26	`#include <string.h>`	26	`#include <string.h>`
27		27
28	`#include "env.h"`	28	`#include "env.h"`
29	`#include "helpers.h"`	29	`#include "helpers.h"`
30		30
31	`#include "rmod.h"`	31	`#include "rmod.h"`
32		32
33	`#include "rmodinit.h"`	33	`#include "rmodinit.h"`
34		34
35		35
36	`/* returns far pointer to rmod's settings block on success */`	36	`/* returns far pointer to rmod's settings block on success */`
37	`struct rmod_props far *rmod_install(unsigned short envsize) {`	37	`struct rmod_props far *rmod_install(unsigned short envsize) {`
38	`char far myptr, far mcb;`	38	`char far myptr, far mcb;`
39	`unsigned short far *owner;`	39	`unsigned short far *owner;`
40	`const unsigned short sizeof_rmodandprops_paras = rmod_len + sizeof(struct rmod_props) + 15 / 16;`	40	`const unsigned short sizeof_rmodandprops_paras = (0x100 + rmod_len + sizeof(struct rmod_props) + 15) / 16;`
41	`unsigned short rmodseg = 0xffff;`	41	`unsigned short rmodseg = 0xffff;`
42	`unsigned short envseg, origenvseg;`	42	`unsigned short envseg, origenvseg;`
43	`struct rmod_props far *res = NULL;`	43	`struct rmod_props far *res = NULL;`
44		44
45	`/* read my current env segment from PSP and save it */`	45	`/* read my current env segment from PSP and save it */`
46	`envseg = ((unsigned short )0x2c);`	46	`envseg = ((unsigned short )0x2c);`
47	`origenvseg = envseg;`	47	`origenvseg = envseg;`
48		48
49	`/* printf("original (PSP) env buffer at %04X\r\n", envseg); */`	49	`/* printf("original (PSP) env buffer at %04X\r\n", envseg); */`
50		50
51	`/* if envseg is zero, then enforce our own one (MSDOS 5 does not provide a default env) */`	51	`/* if envseg is zero, then enforce our own one (MSDOS 5 does not provide a default env) */`
52	`if ((envseg == 0) && (envsize == 0)) envsize = 256;`	52	`if ((envseg == 0) && (envsize == 0)) envsize = 256;`
53		53
54	`/* if custom envsize requested, convert it to number of paragraphs */`	54	`/* if custom envsize requested, convert it to number of paragraphs */`
55	`if (envsize != 0) {`	55	`if (envsize != 0) {`
56	`envsize += 15;`	56	`envsize += 15;`
57	`envsize /= 16;`	57	`envsize /= 16;`
58	`}`	58	`}`
59		59
60	`_asm {`	60	`_asm {`
61	`/* link in the UMB memory chain for enabling high-memory allocation (and save initial status on stack) */`	61	`/* link in the UMB memory chain for enabling high-memory allocation (and save initial status on stack) */`
62	`mov ax, 0x5802 /* GET UMB LINK STATE */`	62	`mov ax, 0x5802 /* GET UMB LINK STATE */`
63	`int 0x21`	63	`int 0x21`
64	`xor ah, ah`	64	`xor ah, ah`
65	`push ax /* save link state on stack */`	65	`push ax /* save link state on stack */`
66	`mov ax, 0x5803 /* SET UMB LINK STATE */`	66	`mov ax, 0x5803 /* SET UMB LINK STATE */`
67	`mov bx, 1`	67	`mov bx, 1`
68	`int 0x21`	68	`int 0x21`
69	`/* get current allocation strategy and save it in DX */`	69	`/* get current allocation strategy and save it in DX */`
70	`mov ax, 0x5800`	70	`mov ax, 0x5800`
71	`int 0x21`	71	`int 0x21`
72	`push ax`	72	`push ax`
73	`pop dx`	73	`pop dx`
74	`/* set strategy to 'last fit, try high then low memory' */`	74	`/* set strategy to 'last fit, try high then low memory' */`
75	`mov ax, 0x5801`	75	`mov ax, 0x5801`
76	`mov bx, 0x0082`	76	`mov bx, 0x0082`
77	`int 0x21`	77	`int 0x21`
78	`/* ask for a memory block and save the given segment to rmodseg */`	78	`/* ask for a memory block and save the given segment to rmodseg */`
79	`mov ah, 0x48`	79	`mov ah, 0x48`
80	`mov bx, sizeof_rmodandprops_paras`	80	`mov bx, sizeof_rmodandprops_paras`
81	`int 0x21`	81	`int 0x21`
82	`jc ALLOC_FAIL`	82	`jc ALLOC_FAIL`
83	`mov rmodseg, ax`	83	`mov rmodseg, ax`
84	`/* ask for a memory block for the environment and save it to envseg (only if custom size requested) */`	84	`/* ask for a memory block for the environment and save it to envseg (only if custom size requested) */`
85	`mov bx, envsize`	85	`mov bx, envsize`
86	`test bx, bx`	86	`test bx, bx`
87	`jz ALLOC_FAIL`	87	`jz ALLOC_FAIL`
88	`mov ah, 0x48`	88	`mov ah, 0x48`
89	`int 0x21`	89	`int 0x21`
90	`jc ALLOC_FAIL`	90	`jc ALLOC_FAIL`
91	`mov envseg, ax`	91	`mov envseg, ax`
92		92
93	`ALLOC_FAIL:`	93	`ALLOC_FAIL:`
94	`/* restore initial allocation strategy */`	94	`/* restore initial allocation strategy */`
95	`mov ax, 0x5801`	95	`mov ax, 0x5801`
96	`mov bx, dx`	96	`mov bx, dx`
97	`int 0x21`	97	`int 0x21`
98	`/* restore initial UMB memory link state */`	98	`/* restore initial UMB memory link state */`
99	`mov ax, 0x5803`	99	`mov ax, 0x5803`
100	`pop bx /* pop initial UMB link state from stack */`	100	`pop bx /* pop initial UMB link state from stack */`
101	`int 0x21`	101	`int 0x21`
102	`}`	102	`}`
103		103
104	`if (rmodseg == 0xffff) {`	104	`if (rmodseg == 0xffff) {`
105	`outputnl("malloc error");`	105	`outputnl("malloc error");`
106	`return(NULL);`	106	`return(NULL);`
107	`}`	107	`}`
108		108
109	`/* copy rmod to its destination */`	109	`/* copy rmod to its destination, prefixed with a copy of my own PSP */`
110	`myptr = MK_FP(rmodseg, 0);`	110	`myptr = MK_FP(rmodseg, 0);`
-		111	`{`
-		112	`unsigned short i;`
-		113	`char mypsp = (void )0;`
-		114	`for (i = 0; i < 0x100; i++) myptr[i] = mypsp[i];`
-		115	`}`
-		116	`myptr = MK_FP(rmodseg, 0x100);`
111	`_fmemcpy(myptr, rmod, rmod_len);`	117	`_fmemcpy(myptr, rmod, rmod_len);`
112		118
113	`/* mark rmod memory as "self owned" */`	119	`/* mark rmod memory as "self owned" */`
114	`mcb = MK_FP(rmodseg - 1, 0);`	120	`mcb = MK_FP(rmodseg - 1, 0);`
115	`owner = (void far *)(mcb + 1);`	121	`owner = (void far *)(mcb + 1);`
116	`*owner = rmodseg;`	122	`*owner = rmodseg;`
117	`_fmemcpy(mcb + 8, "SVARCOM", 8);`	123	`_fmemcpy(mcb + 8, "SVARCOM", 8);`
118		124
119	`/* mark env memory as "owned by rmod" */`	125	`/* mark env memory as "owned by rmod" */`
120	`mcb = MK_FP(envseg - 1, 0);`	126	`mcb = MK_FP(envseg - 1, 0);`
121	`owner = (void far *)(mcb + 1);`	127	`owner = (void far *)(mcb + 1);`
122	`*owner = rmodseg;`	128	`*owner = rmodseg;`
123	`_fmemcpy(mcb + 8, "SVARENV", 8);`	129	`_fmemcpy(mcb + 8, "SVARENV", 8);`
124		130
125	`/* if env block is newly allocated, fill it with a few NULLs */`	131	`/* if env block is newly allocated, fill it with a few NULLs */`
126	`if (envsize != 0) {`	132	`if (envsize != 0) {`
127	`owner = MK_FP(envseg, 0);`	133	`owner = MK_FP(envseg, 0);`
128	`owner[0] = 0;`	134	`owner[0] = 0;`
129	`owner[1] = 0;`	135	`owner[1] = 0;`
130	`}`	136	`}`
131		137
132	`/* prepare result (rmod props) */`	138	`/* prepare result (rmod props) */`
133	`res = MK_FP(rmodseg, rmod_len);`	139	`res = MK_FP(rmodseg, 0x100 + rmod_len);`
134	`_fmemset(res, 0, sizeof(res)); / zero out */`	140	`_fmemset(res, 0, sizeof(res)); / zero out */`
135	`res->rmodseg = rmodseg; /* rmod segment */`	141	`res->rmodseg = rmodseg; /* rmod segment */`
136	`res->inputbuf[0] = 128; /* input buffer for INT 0x21, AH=0Ah*/`	142	`res->inputbuf[0] = 128; /* input buffer for INT 0x21, AH=0Ah*/`
137	`res->echoflag = 1; /* ECHO ON */`	143	`res->echoflag = 1; /* ECHO ON */`
138	`res->origenvseg = origenvseg; /* original environment segment */`	144	`res->origenvseg = origenvseg; /* original environment segment */`
139		145
140	`/* write env segment to rmod buffer */`	146	`/* write env segment to rmod's PSP */`
141	`owner = MK_FP(rmodseg, RMOD_OFFSET_ENVSEG);`	147	`owner = MK_FP(rmodseg, RMOD_OFFSET_ENVSEG);`
142	`*owner = envseg;`	148	`*owner = envseg;`
143		149
144	`/* write boot drive to rmod bootdrive field */`	150	`/* write boot drive to rmod bootdrive field */`
145	`_asm {`	151	`_asm {`
146	`push ax`	152	`push ax`
147	`push bx`	153	`push bx`
148	`push dx`	154	`push dx`
149	`push ds`	155	`push ds`
150	`mov ax, 0x3305 /* DOS 4.0+ - GET BOOT DRIVE */`	156	`mov ax, 0x3305 /* DOS 4.0+ - GET BOOT DRIVE */`
151	`int 0x21 /* boot drive is in DL now (1=A:, 2=B:, etc) */`	157	`int 0x21 /* boot drive is in DL now (1=A:, 2=B:, etc) */`
152	`add dl, 'A'-1 /* convert to a proper ASCII letter */`	158	`add dl, 'A'-1 /* convert to a proper ASCII letter */`
153	`/* set DS to rmodseg */`	159	`/* set DS to rmodseg */`
154	`mov ax, rmodseg`	160	`mov ax, rmodseg`
155	`mov ds, ax`	161	`mov ds, ax`
156	`/* write boot drive to rmod bootdrive field */`	162	`/* write boot drive to rmod bootdrive field */`
157	`mov bx, RMOD_OFFSET_BOOTDRIVE`	163	`mov bx, RMOD_OFFSET_BOOTDRIVE`
158	`mov [bx], dl`	164	`mov [bx], dl`
159	`pop ds`	165	`pop ds`
160	`pop dx`	166	`pop dx`
161	`pop bx`	167	`pop bx`
162	`pop ax`	168	`pop ax`
163	`}`	169	`}`
164		170
165	`/* save my original parent in rmod's memory */`	171	`/* save my original parent in rmod's memory */`
166	`res->origparent = ((unsigned long )0x0a); /* original parent seg:off is at 0x0a of my PSP */`	172	`res->origparent = ((unsigned long )0x0a); /* original parent seg:off is at 0x0a of my PSP */`
167		173
168	`/* set the int22 handler in my PSP to rmod so DOS jumps to rmod after I`	174	`/* set the int22 handler in my PSP to rmod so DOS jumps to rmod after I`
169	`* terminate and save the original handler in rmod's memory */`	175	`* terminate and save the original handler in rmod's memory */`
170	`{`	176	`{`
171	`unsigned short ptr = (void )0x0a; /* int22 handler is at 0x0A of the PSP */`	177	`unsigned short ptr = (void )0x0a; /* int22 handler is at 0x0A of the PSP */`
172	`ptr[0] = RMOD_OFFSET_ROUTINE;`	178	`ptr[0] = RMOD_OFFSET_ROUTINE;`
173	`ptr[1] = rmodseg;`	179	`ptr[1] = rmodseg;`
174	`}`	180	`}`
175		181
176	`return(res);`	182	`return(res);`
177	`}`	183	`}`
178		184
179		185
180	`/* look up my parent: if it's rmod then return a ptr to its props struct,`	186	`/* look up my parent: if it's rmod then return a ptr to its props struct,`
181	`* otherwise return NULL */`	187	`* otherwise return NULL */`
182	`struct rmod_props far *rmod_find(void) {`	188	`struct rmod_props far *rmod_find(void) {`
183	`unsigned short parent = (void )0x0C; /* parent's seg in PSP[Ch] ("prev. int22 handler") */`	189	`unsigned short parent = (void )0x0C; /* parent's seg in PSP[Ch] ("prev. int22 handler") */`
184	`unsigned short far *ptr;`	190	`unsigned short far *ptr;`
185	`const unsigned short sig[] = {0x1983, 0x1985, 0x2017, 0x2019};`	191	`const unsigned short sig[] = {0x1983, 0x1985, 0x2017, 0x2019};`
186	`unsigned char i;`	192	`unsigned char i;`
187	`/* is it rmod? */`	193	`/* is it rmod? */`
188	`ptr = MK_FP(*parent, 0);`	194	`ptr = MK_FP(*parent, 0x100);`
189	`for (i = 0; i < 4; i++) if (ptr[i] != sig[i]) return(NULL);`	195	`for (i = 0; i < 4; i++) if (ptr[i] != sig[i]) return(NULL);`
190	`/* match successfull (rmod is my parent) */`	196	`/* match successfull (rmod is my parent) */`
191	`return(MK_FP(*parent, rmod_len));`	197	`return(MK_FP(*parent, 0x100 + rmod_len));`
192	`}`	198	`}`
193		199
194		200
195	`/* update rmod's pointer to comspec */`	201	`/* update rmod's pointer to comspec */`
196	`void rmod_updatecomspecptr(unsigned short rmod_seg, unsigned short env_seg) {`	202	`void rmod_updatecomspecptr(unsigned short rmod_seg, unsigned short env_seg) {`
197	`unsigned short far *comspecptr = MK_FP(rmod_seg, RMOD_OFFSET_COMSPECPTR);`	203	`unsigned short far *comspecptr = MK_FP(rmod_seg, RMOD_OFFSET_COMSPECPTR);`
198	`char far *comspecfp = env_lookup_val(env_seg, "COMSPEC");`	204	`char far *comspecfp = env_lookup_val(env_seg, "COMSPEC");`
199	`if (comspecfp != NULL) {`	205	`if (comspecfp != NULL) {`
200	`*comspecptr = FP_OFF(comspecfp);`	206	`*comspecptr = FP_OFF(comspecfp);`
201	`} else {`	207	`} else {`
202	`*comspecptr = 0;`	208	`*comspecptr = 0;`
203	`}`	209	`}`
204	`}`	210	`}`
205		211

Subversion Repositories SvarDOS

(root)/svarcom/trunk/rmodinit.c @ 1714 – Rev 454 → 459