diff options
| -rw-r--r-- | comhan.c | 213 | ||||
| -rw-r--r-- | direct.c | 55 | ||||
| -rw-r--r-- | main.c | 22 | ||||
| -rw-r--r-- | mpx.h | 64 | ||||
| -rw-r--r-- | sys_reqc.c | 30 |
5 files changed, 384 insertions, 0 deletions
diff --git a/comhan.c b/comhan.c new file mode 100644 index 0000000..556aab2 --- /dev/null +++ b/comhan.c @@ -0,0 +1,213 @@ +/*
+ * file: comhan.c
+ *
+ * This file is the command handler for the
+ * MPX operating system.
+ */
+
+#include <stdio.h>
+#include <string.h>
+#include "mpx.h"
+
+#define BUF_SIZE 80 /* Size of the command line buffer. */
+#define VERSION 0
+#define DATE 1
+#define DIRECTORY 2
+#define STOP 3
+#define HELP 4
+#define PROMPT 5
+#define ALIAS 6
+
+
+
+int length; /* Length of the command line. */
+
+char prompt[20] = "mpx>";
+const char version[] = "MPX OS - Version 1.0\n";
+char date[] = "01/09/1991";
+
+char *cmds[] = {"version", "date", "directory","stop",
+ "help", "prompt", "alias", NULL};
+char *aliases[] = {"", "", "", "", "", "", "", NULL};
+
+/*
+ * comhan() This is the command handler for the MPX OS.
+ * It repeatedly prints a prompt, makes a system
+ * request to read from the console, and then
+ * carries out the command.
+ *
+ * Parameters: None.
+ * Return value: None.
+ */
+
+void comhan() {
+ char *args[5];
+ int argc;
+ int cmd_num;
+ char buffer[BUF_SIZE];
+
+ do {
+ printf("%s ",prompt); /* Print a prompt. */
+ length = BUF_SIZE; /* Reset length of buffer. */
+ sys_req(CON,READ,buffer,&length); /* Request CON input */
+
+ argc = set_args(buffer, args);
+
+ switch (cmd_num = get_cmd(args[0])) {
+ case VERSION: cmd_version(); break;
+ case DATE: cmd_date(args); break;
+ case DIRECTORY: cmd_directory(); break;
+ case STOP: cmd_stop(); break;
+ case HELP: cmd_help(args); break;
+ case PROMPT: cmd_prompt(args); break;
+ case ALIAS: cmd_alias(args); break;
+ default:
+ printf("Can't recognize.\n");
+ break;
+ }
+ } while (cmd_num != STOP);
+}
+
+int get_cmd(char cmd[]){
+ /* return the number associated with a command (use STOP, HELP etc) */
+
+ int i =0 ; //loop control
+
+ if (cmd == NULL) {
+ return -1;
+ }
+
+ strlwr(cmd);
+
+ while (cmds[i] != NULL) {
+ if (strcmp(cmds[i], cmd)==0 || strcmp(aliases[i], cmd)==0){
+ return i;
+ }
+ i++;
+ }
+
+ //default - means it wasn't a valid command
+ return -1;
+}
+
+int set_args(char buffer[], char *args[]) {
+ /* use string tok to set the contents of args from buffer
+ and return the number of args (will go into argc) */
+ char separators[4] = " =/"; //Characters that separate tokens
+ int i = 0; //loop control
+
+ args[i] = strtok(buffer, separators); //Get first token
+ while(args[i] != NULL){
+ args[++i] = strtok(NULL, separators); //Get next tokens
+ }
+
+ return i;
+}
+/**
+ * Print the version number.
+ */
+void cmd_version() {
+ printf("%s", version);
+}
+
+/**
+ * Print or change the date
+ */
+void cmd_date(char *args[]){
+
+ int m, d, y;
+
+ if (strcmp("", args[1])==0) {
+ printf("%s \n", date);
+ } else {
+
+ m = atoi(args[1]);
+ d = atoi(args[2]);
+ y = atoi(args[3]);
+
+ if (m > 0 && m < 13 && d > 0 && d < 32) {
+ sprintf(date, "%d/%d/%d", m, d, y);
+ printf("Date set to %s \n", date);
+ } else {
+ printf("Invalid date. \n");
+ }
+ }
+}
+void cmd_directory(){
+ int no_proc = directory(direct, DIR_SIZE);
+ int i;
+
+ if (no_proc == 1) {
+ printf("You have 1 program \n");
+ } else if (no_proc == 0) {
+ printf("You have no programs \n");
+ } else {
+ printf("You have %d programs \n", no_proc);
+ }
+
+ if (no_proc > 0) {
+ printf("Size Name \n");
+ printf("===================================== \n");
+ }
+
+ for (i = 0; i < no_proc; i++) {
+ printf("%8d %s \n", direct[i].dirsiz, direct[i].dirnam);
+ }
+}
+
+/**
+ * Print a goodbye message
+ */
+void cmd_stop(){
+ printf("**COMHAN execution complete **\n");
+}
+
+/**
+ * Print information about the COMHAN commands.
+ * Will print all commands or just information specific to the
+ * argument if given.
+ */
+void cmd_help(char *args[]){
+ char ver[] = "version Display version number\n";
+ char hlp[] = "help Provide information about commands\n";
+ char dir[] = "directory List .mpx files\n";
+ char dat[] = "date [mm/dd/yyyy] Display or set the system date\n";
+ char stp[] = "stop Terminate execution of COMHAN\n";
+ char prmpt[] = "prompt string Change the prompt for commands\n";
+ char als[] = "alias command=string Create an alias for a command\n";
+
+ switch(get_cmd(args[1])){
+ case VERSION: printf(ver); break;
+ case DATE: printf(dat); break;
+ case DIRECTORY: printf(dir); break;
+ case STOP: printf(stp); break;
+ case HELP: printf(hlp); break;
+ case PROMPT: printf(prmpt); break;
+ case ALIAS: printf(als); break;
+ default:
+ printf("**\tCommand Summary\t**\n");
+ printf("Name Use\n");
+ printf("======================================\n");
+ printf(ver);
+ printf(dat);
+ printf(dir);
+ printf(stp);
+ printf(hlp);
+ printf(prmpt);
+ printf(als);
+ }
+}
+
+/**
+ * Change the prompt.
+ */
+void cmd_prompt(char *args[]){
+ strcpy(prompt, args[1]);
+}
+
+void cmd_alias(char *args[]){
+ //get the number of the command to alias
+ int num = get_cmd(args[1]);
+ strcpy(aliases[num], args[2]);
+ num ++;
+}
diff --git a/direct.c b/direct.c new file mode 100644 index 0000000..b6181d5 --- /dev/null +++ b/direct.c @@ -0,0 +1,55 @@ +/*
+ * file: direct.c
+ *
+ * This file contains the function which reads the names and
+ * sizes of the MPX/OS process files from the disk, and stores
+ * them in the directory entry array.
+ */
+
+#include <dos.h> /* Borland header file */
+#include <fcntl.h> /* Borland header file */
+#include <string.h> /* Borland header file */
+#include <dir.h> /* Borland header file */
+#include "mpx.h"
+
+dir direct[MAXSIZE]; /* The array of directory entries. */
+
+/*
+ *
+ * directory - This procedure performs a sequential read of the MPX
+ * directory, obtaining all .MPX files up to the size of the
+ * directory. These are the file that can be loaded by
+ * COMHAN. Note that the file specific details are saved in
+ * the dir structure, direct.
+ *
+ * Parameters: direct - the array of directory entries.
+ * dir_size - the capacity of the direct array.
+ *
+ * Return value: The number of files entries made to the
+ * direct array.
+ */
+
+
+int directory(dir *direct, int dir_size)
+{
+ int num_procs; /* Number of .mpx files found. */
+ char filename[15]; /* Name of a file with .mpx extension. */
+ int done; /* Flags when no more .mpx files can be found. */
+ struct ffblk ffblk;
+
+ num_procs = 0; /* number of .MPX file entries placed in directory */
+
+ done = findfirst ("*.MPX",&ffblk,0);
+ while (!done && num_procs < dir_size) {
+ strcpy (filename,ffblk.ff_name);
+ strcpy(direct->dirnam,filename);
+ direct->dirnam[strcspn(filename,".")] = '\0';
+ direct->dirsiz = ffblk.ff_fsize;
+ ++num_procs;
+ direct++;
+ done = findnext(&ffblk);
+ }
+
+ return(num_procs);
+}
+
@@ -0,0 +1,22 @@ +
+/* file: main.c
+ *
+ * This file contains the function main
+ * for the MPX Operating System - this is where
+ * the program's execution begins
+ */
+
+#include <stdio.h>
+#include "mpx.h"
+
+
+int main(void) {
+ printf("... booting MPX\n\n");
+
+ /* Put initialization code here */
+
+ comhan(); /* Execute the command handler */
+
+ return 0;
+}
+
@@ -0,0 +1,64 @@ +/*
+ * file: mpx.h
+ *
+ * Header file for the MPX Operating System.
+ *
+ * This file contains constant, structure and function
+ * prototypes for the MPX Operating System
+ */
+
+/* MPX System request numbers. */
+
+#define EXIT_CODE 0 /* Process requesting termination. code. */
+#define CON 1 /* The console device - keyboard & monitor. */
+#define PRT 2 /* The printer device - LPT1. */
+#define COM 3 /* The serial port - COM1. */
+
+/* MPX System request types. */
+
+#define READ 0 /* Read from device. */
+#define WRITE 1 /* Write to device. */
+#define WAIT 2 /* Semaphore P operation for device. */
+#define SIGNAL 3 /* Semaphore V operation for device. */
+
+
+#define MAXSIZE 20 /* Size of the directory array. */
+
+struct dirstruct { /* Data type for a directory entry. */
+ char dirnam[9]; /* The name of a .mpx file. */
+ int dirsiz; /* The size of the file (in bytes). */
+};
+
+typedef struct dirstruct dir; /* Use dir as the data typer name. */
+
+/* Function prototypes. */
+
+/* main.c */
+int main(void);
+
+/* comhan.c */
+void comhan(void); /* The MPX/OS command handler. */
+int get_cmd(char args[]);
+void cmd_version(void);
+void cmd_date(char *[]);
+void cmd_directory(void);
+void cmd_stop(void);
+void cmd_help(char *[]);
+void cmd_prompt(char *[]);
+void cmd_alias(char *[]);
+void sys_req(int,int,char *,int *); /* MPX system request function. */
+int directory(dir *, int); /* Support function to load the */
+ /* directory array. */
+
+/*
+ * Global variable EXTERN directives.
+ *
+ * These extern declarations allow the variables to be
+ * accessed from any source code file which includes
+ * this header file. The memory space for the variables
+ * is declared in a *.c file.
+ */
+#define DIR_SIZE 20
+
+extern dir direct[]; /* Array of directory entries - see direct.c */
+extern int directory(dir *direct, int dir_size);
diff --git a/sys_reqc.c b/sys_reqc.c new file mode 100644 index 0000000..7856032 --- /dev/null +++ b/sys_reqc.c @@ -0,0 +1,30 @@ +/*
+ * file: sys_reqc.c
+ *
+ * This is the MPX system request function which
+ * uses the C gets function.
+ */
+
+
+
+/* sys_req - implements the MPX system request function.
+ *
+ * Parameters: number - request number: a device or exit code.
+ * type - request type: read, write, wait, signal.
+ * s - address of read/write buffer.
+ * length - address of buffer length variable.
+ *
+ * Return value: None
+ *
+ * In this module, the only system request allowed is to
+ * read from the console (keyboard). This is done using
+ * the standard C function gets().
+ */
+
+
+void sys_req(int number, int type, char *s, int *length)
+{
+ gets(s); /* Read a string from the keyboard. */
+ *length = strlen(s); /* Get its length. */
+}
+
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