Мое домашнее задание - создать оболочку (выполнено) с функцией истории (выполнено), а затем записать историю в файл (где у меня проблемы), чтобы его можно было загрузить при следующем запуске.
Обычно я человек Java, поэтому мне нужно искать почти все функции c. В любом случае, у меня проблемы с записью моего массива строк в файл. По какой-то причине я продолжаю получать странные символы в зависимости от того, какую кодировку я использую.
Например, если я запускаю программу и сразу же завершаю работу, файл истории содержит:
??_?
Если я запускаю ls, а затем завершаю работу, файл истории содержит:
ls
_?
Я удалил процедуры, которые не связаны. Заранее спасибо за любые указатели. Это третий день парирования. Я в своем уме.
#include
/*Had to use \ so that the includes would show here. */
#include \stdlib.h>
#include \signal.h>
#include \sys/types.h>
#include \unistd.h>
#include \string.h>
#include \errno.h>
/*
* Constant Declarations
*/
#define MAX_LINE 80
#define BUFFER_SIZE 50
#define HIST_SIZE 10
static char buffer[BUFFER_SIZE];
char history[HIST_SIZE][BUFFER_SIZE];
int count = 0;
int caught = 0;
char historyFileLoc[] = "./name.history";
void loadHistory() {
int i;
char histCommand[BUFFER_SIZE];
i = 0;
FILE *hisFile = fopen(historyFileLoc, "r");
if( hisFile ) {
/*If a user edits the history file, only the first ten entries will be loaded */
while(!feof(hisFile)) {
if(fscanf(hisFile, "%s\n", histCommand) == 1){
strcpy(history[i], histCommand);
i++;
count++;
}
}
}
if(hisFile != NULL){
if(fclose(hisFile) != 0) {
perror("History file (r) was not closed correctly");
}
}
}
void saveHistory() {
int i;
char buffer[MAX_LINE];
FILE *hisFile = fopen(historyFileLoc, "w");
for(i=0; i < HIST_SIZE; i++){
if(history[i] != '\0') {
strcpy(buffer, history[i]);
/*fwrite(history[i], 1, strlen(history[i]), hisFile);*/
/* fputs(history[i], hisFile);*/
if(buffer != NULL) {
fprintf(hisFile,"%s\n", buffer);
}
}
}
if(fclose(hisFile) != 0) {
perror("History file was not closed correctly");
}
}
/*
* The main() function presents the prompt "sh>" and then invokes setup(), which waits for the
* user to enter a command. The contents of the command entered by the user are loaded into the
* args array. For example, if the user enters ls Ðl at the COMMAND-> prompt, args[0] will be set
* to the string ls and args[1] will be set to the string Ðl. (By ÒstringÓ, we mean a
* null-terminated, C-style string variable.)
*/
int main(void) {
char inputBuffer[MAX_LINE]; /* buffer to hold the command entered */
int background, status; /* equals 1 if a command is followed by '&' */
char *args[MAX_LINE / 2 + 1]; /* command line arguments */
pid_t pid; /* the process's id */
...
}
Дамп истории [] []:
./660_Lab04.c.out
sh ->ls
660_Lab03_Tests.txt Lab 03 Documentation.docx
660_Lab04.c buffer.h
660_Lab04.c.out name.history
660__Lab01.c main.c
660__Lab03.c main_not_mine.c
CSE_660Lab01Documentation.doc
This is where the dump begins minus sh->
sh ->ls
ls
_?
??_?
Остальная часть моего кода. loadHistory и saveHistory находятся до этого:
void printHistory() {
int i;
int j = 0;
int histcount = count;
printf("\n");
for (i=0; i < HIST_SIZE; i++) {
printf("%d. ",histcount); /* Used to print the correct hitory number */
while (history[i][j] != '\n' && history[i][j] != '\0') {
printf("%c",history[i][j]);
j++;
}
printf("\n");
j=0;
histcount--;
if(histcount == 0) {
break;
}
}
printf("\n");
printf("sh -> ");
}
/* the signal handler function */
void handle_SIGINT() {
write(STDOUT_FILENO,buffer,strlen(buffer));
printHistory();
caught = 1;
}
void setup(char inputBuffer[], char *args[], int *background) {
int length, /* # of characters in the command line */
i, /* loop index for accessing inputBuffer array */
start, /* index where beginning of next command parameter is */
ct, /* index of where to place the next parameter into args[] */
k; /* Generic counter */
ct = 0;
/* read what the user enters on the command line */
length = read(STDIN_FILENO, inputBuffer, MAX_LINE);
if(caught == 1) {
length = read(STDIN_FILENO, inputBuffer, MAX_LINE);
caught = 0;
}
/* checks to see if the command is a history retrieval command. If it isn't then add it to the history */
if((strcmp(inputBuffer, "r\n\0") != 0) && (strncmp(inputBuffer, "r x", 2) != 0) ) {
for(i= (HIST_SIZE - 1); i>0; i--) {
strcpy(history[i], history[i-1]);
}
strcpy(history[0], inputBuffer);
count++;
}
start = -1;
if (length == 0) {
saveHistory();
exit(0); /* ^d was entered, end of user command stream */
} else if ((length < 0) && (errno != EINTR)) {
perror("error reading the command");
saveHistory();
exit(-1); /* terminate with error code of -1 */
}
/* Checks to see if r was entered. If so, it copies the command most recently in the input buffer */
if(strcmp(inputBuffer, "r\n\0") == 0) {
strcpy(inputBuffer,history[0]);
/* Checks to see if r x was entered. If so then it searches for the most recent command that begins with x */
} else if(strncmp(inputBuffer, "r x", 2) == 0) {
for(k=0; k < 10; k++){
if(inputBuffer[2] == history[k][0]) {
strcpy(inputBuffer,history[k]);
break;
}
}
}
length = strlen(inputBuffer);
/* examine every character in the inputBuffer */
for (i = 0; i < length; i++) {
switch (inputBuffer[i]) {
case ' ':
case '\t': /* argument separators */
if (start != -1) {
args[ct] = &inputBuffer[start]; /* set up pointer */
ct++;
}
inputBuffer[i] = '\0';
start = -1;
break;
case '\n': /* should be the final char examined */
if (start != -1) {
args[ct] = &inputBuffer[start];
ct++;
}
inputBuffer[i] = '\0';
args[ct] = NULL; /* no more arguments to this command */
break;
case '&':
*background = 1;
inputBuffer[i] = '\0';
break;
default: /* some other character */
if (start == -1) {
start = i;
}
}
args[ct] = NULL; /* just in case the input line was > 80 */
}
}
/* The main() function presents the prompt "sh->" and then invokes setup(), which waits for the user to enter a command. The contents of the command entered by the user are loaded into the args array. For example, if the user enters ls -l at the COMMAND-> prompt, args[0] will be set to the string ls and args[1] will be set to the string -l. (By string, we mean a null-terminated, C-style string variable.) */
int main(void) {
char inputBuffer[MAX_LINE]; /* buffer to hold the command entered */
int background, status; /* equals 1 if a command is followed by '&' */
char *args[MAX_LINE / 2 + 1]; /* command line arguments */
pid_t pid; /* the process's id */
/* set up the signal handler */
struct sigaction handler;
handler.sa_handler = handle_SIGINT;
sigaction(SIGINT, &handler, NULL);
loadHistory();
while (1) {
background = 0;
printf("\nsh ->");
fflush(0);
setup(inputBuffer, args, &background); /* get next command */
fflush(0);
pid = fork(); /* assign the process id */
if (pid < 0) {
fprintf(stderr, "ERROR: Could not properly fork.");
saveHistory();
exit(-1); /* unsucessful exit because the fork could not be created */
} else if (pid == 0) { /* PID was forked successfully */
status = execvp(*args, args); /* execute the command */
if (status < 0) {
fprintf(stderr, "ERROR: Could not execute %s", args[0]);
saveHistory();
exit(1);
}
} else if (background == 0) { /* if the fork is run in the foreground */
wait(NULL);
}
}
return EXIT_SUCCESS;
}