finish ed

This commit is contained in:
Murphy 2023-04-30 14:50:00 -04:00
parent 191bf86ef2
commit 91e701881e
3 changed files with 255 additions and 24 deletions

View file

@ -4,7 +4,7 @@
A terrible busybox/gnu coreutils clone.
Currently the only supported commands are:
`dd`, `cat`, `yes`, `echo`, `printf`, `id`, `groups`, `ls`, `tail`, `head`
`dd`, `cat`, `yes`, `echo`, `printf`, `id`, `groups`, `ls`, `tail`, `head`, `ed`
## How to

View file

@ -4,6 +4,7 @@
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#define INPUT_LEN 1024
@ -12,11 +13,14 @@ static unsigned long line_capacity;
static unsigned long line_count;
static unsigned long line_current;
static bool pending_writes;
static char* default_filename = NULL;
static re_t last_regex = NULL;
enum LineAddressType {
INDEX,
RANGE,
SET,
FREE
};
struct LineAddress {
@ -64,6 +68,8 @@ static bool parse_regex(char** end, struct LineAddress* address, enum RegexDirec
long int* buf = malloc(cap * sizeof(unsigned long));
re_t regex = re_compile(regex_str);
last_regex = regex;
unsigned long i = (dir == ALL ? 0 : line_current);
unsigned long until = (dir == BEFORE ? 0 : line_count - 1);
for (; (dir == BEFORE ? i >= until : i < until); dir == BEFORE ? i-- : i++) {
@ -81,6 +87,7 @@ static bool parse_regex(char** end, struct LineAddress* address, enum RegexDirec
if (dir == BEFORE && i == 0) break;
}
address->empty = false;
address->type = SET;
address->data.set.s = siz;
address->data.set.c = cap;
@ -207,19 +214,26 @@ static bool read_address(char** command, bool whitespace, struct LineAddress* a)
static void free_address (struct LineAddress address) {
if (address.type != SET) return;
address.type = FREE;
free(address.data.set.b);
}
static void free_data() {
if (lines == NULL) return;
for (unsigned long i = 0; i < line_count; i++)
static void free_data(bool all) {
if (lines != NULL) {
for (unsigned long i = 0; i < line_count; i++) {
free(lines[i]);
}
free(lines);
lines = NULL;
}
if (all && default_filename != NULL) {
free(default_filename);
default_filename = NULL;
}
}
static void load_empty() {
free_data();
free_data(false);
line_capacity = 8;
lines = malloc(sizeof(char*) * line_capacity);
@ -275,19 +289,20 @@ int ed_getline(char *buf, size_t size) {
}
static void load_file(FILE* file) {
free_data();
free_data(false);
line_current = 0;
get_input(file, &lines, &line_capacity, &line_count);
if (file != stdin)
fclose(file);
}
static bool check_if_sure() {
static bool check_if_sure(char* prompt) {
if (!pending_writes) {
return true;
}
printf("Do you really want to quit? ");
printf("%s", prompt);
fflush(stdout);
char buf[INPUT_LEN];
@ -352,6 +367,7 @@ static bool handle_append(struct LineAddress* address) {
get_input(stdin, &buf, &cap, &size);
if (size > 0) {
append_lines(address->data.index.i + 1, buf, size);
printf("ed: appened %lu lines\n", size);
}
line_current += size;
free(buf);
@ -365,18 +381,143 @@ static bool handle_delete(struct LineAddress* address) {
}
if (address->type == INDEX) {
delete_lines(address->data.index.i, address->data.index.i);
printf("ed: deleted line %ld\n", address->data.index.i+1);
} else if (address->type == RANGE) {
delete_lines(address->data.range.a, address->data.range.b);
printf("ed: deleted lines %ld-%ld\n", address->data.range.a+1, address->data.range.b+1);
} else if (address->type == SET) {
for (unsigned long i = 0; i < address->data.set.s; i++) {
delete_lines(address->data.set.b[i], address->data.set.b[i]);
}
printf("ed: deleted %lu lines\n", address->data.set.s);
}
return true;
}
static bool get_file_name(char** filename) {
size_t len = strlen(*filename);
if (len < 1 || (len == 1 && **filename == '\n')) {
if (default_filename == NULL) {
fprintf(stderr, "error: no default filename specified\n");
return false;
}
*filename = default_filename;
} else {
if ((*filename)[len - 1] == '\n') {
(*filename)[len - 1] = '\0';
len--;
}
if (default_filename != NULL) {
default_filename = realloc(default_filename, len + 1);
} else {
default_filename = malloc(len + 1);
}
memcpy(default_filename, *filename, len + 1);
*filename = default_filename;
}
return true;
}
static void write_file(char* filename, struct LineAddress* address, char* type) {
if (line_count < 1) {
fprintf(stderr, "error: cannot write empty file\n");
return;
}
if (!get_file_name(&filename)) return;
FILE* file = get_file_s(filename, type);
if (file == NULL) return;
int wrote = 0;
if (address->empty) {
for (unsigned long i = 0; i < line_count; i++) {
fprintf(file, "%s", lines[i]);
wrote++;
}
} else if (address->type == INDEX) {
long int i = address->data.index.i;
fprintf(file, "%s", lines[i]);
wrote++;
} else if (address->type == RANGE) {
for (long int i = address->data.range.a; i < address->data.range.b; i++) {
fprintf(file, "%s", lines[i]);
wrote++;
}
} else if (address->type == SET) {
for (unsigned long i = 0; i < address->data.set.s; i++) {
fprintf(file, "%s", lines[address->data.set.b[i]]);
wrote++;
}
}
pending_writes = false;
fclose(file);
printf("ed: wrote %d lines from %s\n", wrote, filename);
}
static void read_file(char* filename) {
if (!get_file_name(&filename)) return;
FILE* file = get_file_s(filename, "r");
if (file == NULL) return;
unsigned long capacty = 8;
unsigned long size = 0;
char** buf = malloc(capacty * sizeof(char*));
get_input(file, &buf, &capacty, &size);
if (size < 1) {
free(buf);
fprintf(stderr, "error: attempted to read a empty file\n");
return;
}
long int line = -1;
if (line_count > 0) {
line = line_count - 1;
}
append_lines(line, buf, size);
free(buf);
printf("ed: read and appended %lu lines from %s\n", size, filename);
}
static void expand_string(char** buf, int* capacity, int* size, char* text, int len) {
if (*size + len >= *capacity) {
*capacity *= 2;
if (*capacity < *size + len) *capacity = *size + len;
*buf = realloc(*buf, *capacity);
}
memcpy(*buf + *size, text, len);
*size += len;
}
static int substute_string(long int index, long int matches, re_t regex, char* sub, int sub_len) {
int capacity = 8;
int size = 0;
char* buf = malloc(sizeof(char) * capacity);
int offset = 0;
int matches_found = 0;
while(true) {
if (lines[index][offset] == '\0') break;
if (matches_found >= matches && matches > 0) break;
int distance, len;
if ((distance = re_matchp(regex, &lines[index][offset], &len)) == -1) {
break;
}
if (distance > 0)
expand_string(&buf, &capacity, &size, &lines[index][offset], distance);
expand_string(&buf, &capacity, &size, sub, sub_len);
offset += len + distance;
matches_found++;
}
long int left = strlen(lines[index] + offset);
expand_string(&buf, &capacity, &size, &lines[index][offset], left + 1);
free(lines[index]);
lines[index] = buf;
return matches_found;
}
static void prompt() {
printf("%ld: ", line_current + 1);
printf(": ");
fflush(stdout);
char buf[INPUT_LEN];
@ -422,9 +563,11 @@ static void prompt() {
return;
}
bool linenumbers = false;
test:
switch (cmd) {
case '\n':
case '\0':
case '\n':
if (address.empty) {
if (line_current == line_count) {
fprintf(stderr, "error: line number %ld does not exist\n", line_current + 1);
@ -460,45 +603,132 @@ static void prompt() {
address.data.index.i = line_current - 1;
handle_append(&address);
break;
case 'n':
linenumbers = true;
__attribute__((fallthrough));
case 'p':
if (address.empty && address.data.index.i >= (long int) line_count) {
fprintf(stderr, "error: line number %ld does not exist\n", address.data.index.i + 1);
break;
}
if (address.type == INDEX) {
if (linenumbers) printf("%ld\t", address.data.index.i + 1);
printf("%s", lines[address.data.index.i]);
} else if (address.type == RANGE) {
for (long int i = address.data.range.a; i <= address.data.range.b; i++) {
if (linenumbers) printf("%ld\t", i + 1);
printf("%s", lines[i]);
}
} else if (address.type == SET) {
for (unsigned long i = 0; i < address.data.set.s; i++) {
if (linenumbers) printf("%ld\t", i +1);
printf("%s", lines[address.data.set.b[i]]);
}
}
break;
case 'q':
if(check_if_sure()) {
free_address(address);
free_data();
exit(EXIT_SUCCESS);
};
break;
if (!check_if_sure("Quit for sure? ")) break;
__attribute__((fallthrough));
case 'Q':
free_address(address);
free_data();
free_data(true);
exit(EXIT_SUCCESS);
break;
case 'g':
skip_whitespace(&index);
free_address(address);
if (*(index++) != '/') {
fprintf(stderr, "error: unexpected character at start or regex\n");
fprintf(stderr, "error: unexpected character at start of regex\n");
break;
}
if (!parse_regex(&index, &address, ALL)) { return; }
for (unsigned long i = 0; i < address.data.set.s; i++) {
printf("%s", lines[address.data.set.b[i]]);
skip_whitespace(&index);
if (*index == '\n' || *index == '\0') {
cmd = 'p';
} else {
cmd = *(index++);
}
goto test;
break;
case 's':
skip_whitespace(&index);
free_address(address);
if (*(index++) != '/') {
fprintf(stderr, "error: unexpected character at start of regex\n");
break;
}
if (!parse_regex(&index, &address, ALL)) { return; }
char* replace = index;
while(*index != '\0' && *index != '/') index++;
if (*index != '/') {
fprintf(stderr, "error: / missing after %c\n", *index);
break;
}
if (address.data.set.s < 1) {
printf("ed: no matches found\n");
break;
}
*(index++) = '\0';
long int matches;
if (*index == '\0') {
matches = 1;
} else if (*index == 'g') {
matches = -1;
} else {
char* end;
matches = strtol(index, &end, 10);
if (end == index) {
fprintf(stderr, "error: invalid number: %s\n", index);
break;
}
}
long int sub_len = strlen(replace);
long int matches_found = 0;
for (unsigned long i = 0; i < address.data.set.s; i++) {
matches_found += substute_string(address.data.set.b[i], matches, last_regex, replace, sub_len);
}
printf("ed: replaced %ld matches over %ld lines\n", matches_found, address.data.set.s);
pending_writes = true;
break;
case 'w': {
bool quit = false;
if (*index == 'q') {
index++;
quit = true;
}
skip_whitespace(&index);
write_file(index, &address, "w");
if (quit) {
free_address(address);
free_data(true);
exit(EXIT_SUCCESS);
}
break;
}
case 'r': {
skip_whitespace(&index);
read_file(index);
break;
}
case 'e':
if (!check_if_sure("Load new file for sure? ")) break;
__attribute__((fallthrough));
case 'E': {
skip_whitespace(&index);
char* filename = index;
if(!get_file_name(&filename)) break;
FILE* file = get_file_s(filename, "r");
if (file == NULL) break;
load_file(file);
break;
}
case 'W':
skip_whitespace(&index);
write_file(index, &address, "a");
break;
case '=':
printf("%ld\n", line_current + 1);
break;
default:
fprintf(stderr, "error: unimplemented command\n");
@ -522,6 +752,7 @@ COMMAND(ed) {
} else {
FILE* file = get_file(argv[0], "r");
load_file(file);
get_file_name(&argv[0]);
prompt_loop();
}
return EXIT_SUCCESS;

View file

@ -32,7 +32,7 @@ FILE* get_file_s(const char* path, const char* type) {
read:
file = fopen(path, type);
if (file == NULL) {
fprintf(stderr, "error: failed to open file %s: %s\n", path, strerror(errno));
fprintf(stderr, "error: failed to %s file %s: %s\n", type[0] == 'r' ? "read" : "write", path, strerror(errno));
}
return file;
}