more documentation

This commit is contained in:
Murphy 2023-06-07 21:33:44 -04:00
parent 67173fb971
commit 47e9c33362
7 changed files with 217 additions and 96 deletions

View file

@ -1,5 +1,6 @@
/**
* file: cat.c
* command: cat
* author: Tyler Murphy
*/

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@ -1,5 +1,6 @@
/**
* file: chmod.c
* command: chmod
* author: Tyler Murphy
*/

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@ -1,5 +1,6 @@
/**
* file: chown.c
* command: chown
* author: Tyler Murphy
*/

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@ -1,3 +1,9 @@
/**
* file: cp.c
* command: cp
* author: Tyler Murphy
*/
#include "command.h"
#include "lslib.h"
@ -10,14 +16,20 @@
#include <errno.h>
#include <unistd.h>
/**
* Command flags to be used with cp
*/
static struct {
bool recurse;
bool preserve;
bool sym_link;
bool hard_link;
bool verbose;
bool recurse; /* Recurse copy directorys */
bool preserve; /* Preserve file attributes */
bool sym_link; /* Symlink files instead of copy */
bool hard_link; /* Hardlink files instead of copy */
bool verbose; /* Verbose the output */
} flags;
/**
* Help function for cp
*/
static void help(void) {
printf("Usage: cp [-rplsv] SOURCE... DEST\n\n");
printf("Copy SOURCEs to DEST\n\n");
@ -27,6 +39,12 @@ static void help(void) {
printf("\t-v\tVerbose\n");
}
/**
* Takes in each argument that has a single - and parses it
* @param c the character after the -
* @param next the next argument in argv that hasnt been parsed
* @reutrn if the next arg was used or if the arg was invalid
*/
static int short_arg(char c, char* next) {
UNUSED(next);
switch (c) {
@ -54,24 +72,33 @@ static int short_arg(char c, char* next) {
return ARG_UNUSED;
}
/**
* Takes in two files paths and copies the data from one path to another
* @param from the file to copy from
* @param to the file to copy to
* @returns if the file successfully coppied
*/
static bool copy_file(char* from, char* to) {
#define BS 1024
#define BS 1024 /* The block size of copy with */
FILE *from_f, *to_f;
char buf[BS];
int read;
FILE *from_f, *to_f; /* file pointers to cope data from and to */
char buf[BS]; /* te file copy buffer */
int read; /* the amount of bytes read */
/* attempt to get a read stream from the src file */
from_f = get_file_s(from, "r");
if (from_f == NULL) { return false; }
/* attempt to get a write streams from the dest file */
to_f = get_file_s(to, "w");
if (to_f == NULL) { fclose(from_f); return false; }
/* while data is read copy the data to the dest */
while ((read = fread(buf, 1, BS, from_f)) > 0) {
fwrite(buf, 1, read, to_f);
}
/* output if verbose */
if (flags.verbose) {
output("copied '%s'", from);
}
@ -79,164 +106,206 @@ static bool copy_file(char* from, char* to) {
return true;
}
/**
* Takes in two file paths and symlinks from one to the other path
* @param from the file to symlink
* @param to the path to put the symlink
* @returns if the file successfully symlinked
*/
static bool symlink_file(char* from, char* to) {
/* symlink the file and error if failed */
if (symlink(from, to) < 0) {
error_s("failed to symlink '%s'", from);
return false;
} else if (flags.verbose) {
output("symlinked '%s'", from);
output("symlinked '%s'", from); /* output if verbose */
}
return true;
}
/**
* Takes in two file paths and hardlinks from one to the other path
* @param from the file to hardlink
* @param the path to put the hardlink
* @returns fi the fule successfully hardlinked
*/
static bool hardlink_file(char* from, char* to) {
/* hard link the file and error if failed */
if (link(from, to) < 0) {
error_s("failed to hardlink '%s'", from);
return false;
} else if (flags.verbose) {
output("hardlinked '%s'", from);
output("hardlinked '%s'", from); /* output if verbose */
}
return true;
}
/**
* Copies data from one path to another using the set path buffers and
* flags. Make sure to set these before running this function.
* @param s the stat of the file being coppied
*/
static void run_copy(struct stat* s) {
/* read file paths from the path buffers */
char* from = get_path_buffer();
char* to = get_path_buffer_2();
/* choose copy method based on given flags */
bool result;
if (flags.sym_link) {
result = symlink_file(from, to);
if (flags.sym_link) {
result = symlink_file(from, to); /* symlink */
} else if (flags.hard_link) {
result = hardlink_file(from, to);
result = hardlink_file(from, to); /* hardlink */
} else {
result = copy_file(from, to);
result = copy_file(from, to); /* copy */
}
/* if failed return */
if (!result) return;
if (!flags.preserve) return;
/* if set to preserve file attribs, copy over ownership and permissions */
if (chmod(to, s->st_mode) < 0) {
error_s("cannot chmod '%s'", to);
error_s("cannot chmod '%s'", to); /* error if failed */
return;
}
if (chown(to, s->st_uid, s->st_gid) < 0) {
error_s("cannot chown '%s'", to);
error_s("cannot chown '%s'", to); /* error if failed */
return;
}
}
/* predefine function definition */
static void cp_file(char* path);
/**
* Copies all files in a diretory specified in the path buffer, to the dest.
* Make sure both the src and dest path buffers are set before calling.
* @param s the stat of the directory
*/
static void cp_directory(struct stat* s) {
DIR* d;
struct dirent* file;
/* if were not recursing ignore directory and error */
if (!flags.recurse) {
error_s("-r not specified; omitting directory '%s'", get_path_buffer());
return;
}
/* if we failed to make the directory to copy data into error and return */
if (mkdir(get_path_buffer_2(), s->st_mode) < 0 && errno != EEXIST) {
error_s("cannot create directory '%s'", get_path_buffer_2());
return;
}
/* open directory, if failed error and return */
d = opendir(get_path_buffer());
if (d == NULL) {
error_s("cannot open directory '%s'", get_path_buffer());
return;
}
/* copy each file in the directory */
while ((file = readdir(d)) != NULL) {
if (is_dot_dir(file->d_name)) continue;
cp_file(file->d_name);
}
}
static char* get_file_name(char* path) {
int last = 0;
int i = 0;
if (path[0] == '\0') return path;
while (true) {
if (path[i+1] == '\0') break;
if (path[i] == '/') {
last = i;
}
i++;
}
if (last == 0) return path;
else return path + last + 1;
}
/**
* Copies a given file path to the destination given in the 2nd path buffer
* Make sure path buffer 2 is set before running this function
* @param path the file to copy
*/
static void cp_file(char* path) {
/* load src and dest into path buffers */
int save = push_path_buffer(path);
int save2 = push_path_buffer_2(get_file_name(path));
int save2 = push_path_buffer_2(get_last_component(path));
/* if we cannot get file info error and return */
struct stat s;
if (lstat(get_path_buffer(), &s) < 0) {
pop_path_buffer(save);
error_s("cannot stat '%s'", get_path_buffer());
return;
}
/* if the file is a directory copy it as a directory, else copy it as a file */
if (S_ISDIR(s.st_mode)) {
cp_directory(&s);
} else {
run_copy(&s);
}
/* cleanup */
pop_path_buffer(save);
pop_path_buffer_2(save2);
}
/**
* Copes file from a src path to a dest path
*/
COMMAND(cp_main) {
int start, i;
struct stat s;
/* define default flags */
flags.hard_link = false;
flags.sym_link = false;
flags.preserve = false;
flags.recurse = false;
flags.verbose = false;
/* parse arguments */
start = parse_args(argc, argv, help, short_arg, NULL);
/* if not enough arguments passed show help message and quit */
if (argc - start < 2) {
global_help(help);
}
/* only when 2 args and first is a file, the 2nd will be a file */
if (argc - start == 2) {
/* if cannot read file info error and exit */
struct stat s;
if (lstat(argv[start], &s) < 0) {
error("cannot stat '%s'", argv[start]);
}
/* load src and dest into path buffers */
push_path_buffer(argv[argc-2]);
push_path_buffer_2(argv[argc-1]);
/* if the file is a directory copy it as a directory, else copy it as a file */
if (!S_ISDIR(s.st_mode)) {
run_copy(&s);
} else {
cp_directory(&s);
}
/* no need to cleanup path buffers since command is done */
return EXIT_SUCCESS;
}
/* otherwise treat the dest argument as a directory */
/* push directory */
/* push dest directory */
push_path_buffer_2(argv[argc-1]);
/* if we cannot read dest info error and return */
if (lstat(get_path_buffer_2(), &s) < 0) {
error("target: '%s'", get_path_buffer_2());
}
/* copy each file into dest directory */
for (i = start; i < argc - 1; i++) {
cp_file(argv[i]);
}

View file

@ -1,8 +1,17 @@
/**
* file: dd.c
* command: dd
* author: Tyler Murphy
*/
#include "command.h"
#include "lslib.h"
#include <stdlib.h>
/**
* Help function for dd
*/
static void help(void) {
printf("Usage: dd [if=FILE] [of=FILE] [bs=N] [count=N]\n\n");
printf("Copy a file with converting and formatting\n\n");
@ -12,49 +21,57 @@ static void help(void) {
printf("\tcount=N\t\tCopy only N input blocks\n");
}
/**
* Copys a file with converting and formatting
*/
COMMAND(dd_main) {
FILE* in_file = stdin;
FILE* out_file = stdout;
int bs = 1024;
int count = -1;
FILE* in_file = stdin; /* the file to copy from */
FILE* out_file = stdout; /* the file to copy to */
int bs = 1024; /* the default bs */
int count = -1; /* amount of bs's to copy, if negative go until EOF */
int i;
char* buffer;
char* buffer; /* buffer to hold copy data */
size_t read;
/* parse arguments and only check for --help */
parse_help(argc, argv, help);
/* dd doesnt use standard arguments, parse though each argument and match each arg */
for (i = 0; i < argc; i++) {
if (prefix("if=", argv[i])) {
char* path = argv[i] + 3;
if (prefix("if=", argv[i])) { /* sets the input file */
char* path = argv[i] + 3; /* get data after = */
in_file = get_file(path, "rb");
} else if (prefix("of=", argv[i])) {
char* path = argv[i] + 3;
} else if (prefix("of=", argv[i])) { /* sets the output file */
char* path = argv[i] + 3; /* get data after = */
out_file = get_file(path, "wb");
} else if (prefix("bs=", argv[i])) {
char* str = argv[i] + 3;
bs = get_number(str);
if (bs < 1) {
} else if (prefix("bs=", argv[i])) { /* sets the blocksize */
char* str = argv[i] + 3; /* get data after = */
bs = get_blkm(str);
if (bs < 1) { /* cannot have a negative bs */
error("block size must be greater than 0");
}
} else if (prefix("count=", argv[i])) {
char* str = argv[i] + 6;
} else if (prefix("count=", argv[i])) { /* sets the count of bs to do */
char* str = argv[i] + 6; /* get data after = */
count = get_number(str);
if (count < 1) {
error("count must be greather than 0");
}
} else {
} else { /* error and exit since arg is invalid */
error("unkown option %s", argv[i]);
}
}
/* allocate buffer of set bs */
buffer = xalloc(bs);
/* read data until EOF from and to buf */
while ((read = fread(buffer, 1, bs, in_file)) != 0) {
fwrite(buffer, 1, read, out_file);
if (--count, count == 0) break;
}
/* cleanup */
free(buffer);
fclose(in_file);
fclose(out_file);

View file

@ -1,31 +1,47 @@
/**
* file: echo.c
* command: echo
* author: Tyler Murphy
*/
#include "command.h"
#include "lslib.h"
#include <stdlib.h>
/**
* Flags that are to be used with echo
*/
static struct {
bool escape_codes;
bool newline;
} flags;
/**
* Prints a null terminated string to standard out and changes each char based on input flags
* @param str the string to print
*/
static void print_with_escape_codes(const char* str) {
size_t index = 0;
char n;
size_t index = 0; /* current index in the string */
char c; /* current char being read */
char n; /* next char being read */
while (true) {
char c = str[index];
c = str[index]; /* read current char */
index++;
if (c == '\0') break;
if (c != '\\') {
if (c == '\0') break; /* if we hit the NUL, break */
if (c != '\\') { /* if its not a escaped code, print and continue */
putchar(c);
continue;
}
/* read next character */
n = str[index];
index++;
/* check each char against the valid escape codes */
switch (n) {
case '\\':
putchar('\\');
@ -47,13 +63,19 @@ static void print_with_escape_codes(const char* str) {
case 'v':
putchar('\v');
break;
default:
default: /* if none found print both chars as is */
putchar(c);
putchar(n);
}
}
}
/**
* Takes in each argument that has a single - and parses it
* @param c the character after the -
* @param next the next argument in argv that hasnt been parsed
* @reutrn if the next arg was used or if the arg was invalid
*/
static int short_arg(char c, char* next) {
UNUSED(next);
switch (c) {
@ -74,19 +96,26 @@ static int short_arg(char c, char* next) {
return ARG_UNUSED;
}
/**
* Prints data in each argument to stdout
*/
COMMAND(echo_main) {
int start, i;
/* if no arguments supplied exit */
if (argc < 1) {
return EXIT_SUCCESS;
return EXIT_FAILURE;
}
/* set default flags */
flags.escape_codes = false;
flags.newline = true;
/* parse arguments, no help message */
start = parse_args(argc, argv, NULL, short_arg, NULL);
/* for each argument either print as is or parse each character for escape codes */
for (i = start; i < argc; i++) {
if (flags.escape_codes) {
print_with_escape_codes(argv[i]);
@ -94,14 +123,17 @@ COMMAND(echo_main) {
printf("%s", argv[i]);
}
/* put a space seperator between arguments */
if (i + 1 != argc) {
putchar(' ');
}
}
/* if set to put a new line at the end (default), do so */
if (flags.newline) {
putchar('\n');
}
/* done */
return EXIT_SUCCESS;
}

View file

@ -53,7 +53,7 @@ static bool read_regex(char** end, re_t* regex, enum RegexDirection dir) {
while(true) {
c = *(index++);
if (c == '\0') {
error_s("missing regex after %c\n", dir == BEFORE ? '?' : '/');
error_s("missing regex after %c", dir == BEFORE ? '?' : '/');
return false;
}
if (c == (dir == BEFORE ? '?' : '/')) {
@ -186,7 +186,7 @@ static bool read_address(char** command, bool whitespace, struct LineAddress* a)
n_pre = -1;
} else {
if (n_pre < 0) {
error_s("input cannot be negative\n");
error_s("input cannot be negative");
return false;
}
index = end_pre;
@ -222,7 +222,7 @@ static bool read_address(char** command, bool whitespace, struct LineAddress* a)
}
if (address.data.index.i < 0) {
error_s("line number %ld does not exist\n", address.data.index.i + 1);
error_s("line number %ld does not exist", address.data.index.i + 1);
return false;
}
@ -236,7 +236,7 @@ static bool read_address(char** command, bool whitespace, struct LineAddress* a)
n = strtol(index, &end, 10) - 1;
if (n < 0) {
error_s("input cannot be negative\n");
error_s("input cannot be negative");
return false;
}
if (index == end) {
@ -245,7 +245,7 @@ static bool read_address(char** command, bool whitespace, struct LineAddress* a)
address.data.index.i = line_current + n;
}
if (address.data.index.i >= (long int) line_count) {
error_s("line number %ld does not exist\n", address.data.index.i + 1);
error_s("line number %ld does not exist", address.data.index.i + 1);
return false;
}
break;
@ -281,7 +281,7 @@ static bool read_address(char** command, bool whitespace, struct LineAddress* a)
address.data.index.i = n_pre;
}
if (address.data.index.i < 0 || address.data.index.i >= (long int) line_count) {
error_s("line number %ld does not exist\n", address.data.index.i + 1);
error_s("line number %ld does not exist", address.data.index.i + 1);
return false;
}
}
@ -437,7 +437,7 @@ static bool handle_append(struct LineAddress* address) {
unsigned long cap, size;
if (address->type != INDEX) {
error_s("append command requires index addressing\n");
error_s("append command requires index addressing");
return false;
}
@ -449,7 +449,7 @@ static bool handle_append(struct LineAddress* address) {
if (size > 0) {
append_lines(address->data.index.i + 1, buf, size);
printf("ed: appened %lu lines\n", size);
output("appened %lu lines", size);
}
line_current += size;
@ -459,22 +459,22 @@ static bool handle_append(struct LineAddress* address) {
static bool handle_delete(struct LineAddress* address) {
if (address->empty && address->data.index.i >= (long int) line_count) {
error_s("line number %ld does not exist\n", address->data.index.i + 1);
error_s("line number %ld does not exist", address->data.index.i + 1);
return false;
}
if (address->type == INDEX) {
delete_lines(address->data.index.i, address->data.index.i);
output("deleted line %ld\n", address->data.index.i+1);
output("deleted line %ld", address->data.index.i+1);
} else if (address->type == RANGE) {
delete_lines(address->data.range.a, address->data.range.b);
output("deleted lines %ld-%ld\n", address->data.range.a+1, address->data.range.b+1);
output("deleted lines %ld-%ld", address->data.range.a+1, address->data.range.b+1);
} else if (address->type == SET) {
unsigned long i;
for (i = 0; i < address->data.set.s; i++) {
delete_lines(address->data.set.b[i], address->data.set.b[i]);
}
output("deleted %lu lines\n", address->data.set.s);
output("deleted %lu lines", address->data.set.s);
}
return true;
@ -485,7 +485,7 @@ static bool get_file_name(char** filename) {
if (len < 1 || (len == 1 && **filename == '\n')) {
if (default_filename == NULL) {
error_s("no default filename specified\n");
error_s("no default filename specified");
return false;
}
*filename = default_filename;
@ -510,7 +510,7 @@ static void write_file(char* filename, struct LineAddress* address, char* type)
int wrote;
if (line_count < 1) {
error_s("cannot write empty file\n");
error_s("cannot write empty file");
return;
}
@ -546,7 +546,7 @@ static void write_file(char* filename, struct LineAddress* address, char* type)
pending_writes = false;
fclose(file);
output("wrote %d lines from %s\n", wrote, filename);
output("wrote %d lines from %s", wrote, filename);
}
static void read_file(char* filename) {
@ -566,7 +566,7 @@ static void read_file(char* filename) {
if (size < 1) {
free(buf);
error_s("attempted to read a empty file\n");
error_s("attempted to read a empty file");
return;
}
@ -577,7 +577,7 @@ static void read_file(char* filename) {
append_lines(line, buf, size);
free(buf);
output("read and appended %lu lines from %s\n", size, filename);
output("read and appended %lu lines from %s", size, filename);
}
static void expand_string(char** buf, int* capacity, int* size, char* text, int len) {
@ -650,7 +650,7 @@ static void prompt(void) {
struct LineAddress address2;
if (address.type != INDEX) {
error_s("comma range addressing requires two index addresses\n");
error_s("comma range addressing requires two index addresses");
free_address(address);
return;
}
@ -663,7 +663,7 @@ static void prompt(void) {
}
if (address2.type != INDEX) {
error_s("comma range addressing requires two index addresses\n");
error_s("comma range addressing requires two index addresses");
free_address(address);
free_address(address2);
return;
@ -677,7 +677,7 @@ static void prompt(void) {
}
if (address.type == RANGE && address.data.range.a > address.data.range.b) {
error_s("range addressing must be in ascending order\n");
error_s("range addressing must be in ascending order");
free_address(address);
return;
}
@ -690,10 +690,10 @@ test:
case '\n':
if (address.empty) {
if (line_current == line_count) {
error_s("line number %ld does not exist\n", line_current + 1);
error_s("line number %ld does not exist", line_current + 1);
break;
} else if (line_current + 1 == line_count) {
error_s("line number %ld does not exist\n", line_current + 2);
error_s("line number %ld does not exist", line_current + 2);
break;
} else {
line_current++;
@ -706,7 +706,7 @@ test:
} else if (address.type == RANGE) {
line_current = address.data.range.b;
} else if (address.type == SET) {
error_s("unexpected range addressing\n");
error_s("unexpected range addressing");
break;
}
printf("%s", lines[line_current]);
@ -728,7 +728,7 @@ test:
__attribute__((fallthrough));
case 'p':
if (address.empty && address.data.index.i >= (long int) line_count) {
error_s("line number %ld does not exist\n", address.data.index.i + 1);
error_s("line number %ld does not exist", address.data.index.i + 1);
break;
}
if (address.type == INDEX) {
@ -779,17 +779,17 @@ test:
skip_whitespace(&index);
if (*(index++) != '/') {
error_s("unexpected character at start of regex\n");
error_s("unexpected character at start of regex");
break;
}
if (!parse_regex_lines(&index, &address)) { return; }
while(*index != '\0' && *index != '/') index++;
if (*index != '/') {
error_s("/ missing after %c\n", *index);
error_s("/ missing after %c", *index);
break;
}
if (address.data.set.s < 1) {
error_s("no matches found\n");
error_s("no matches found");
break;
}
*(index++) = '\0';
@ -801,11 +801,11 @@ test:
char* end;
matches = strtol(index, &end, 10);
if (end == index) {
error_s("invalid number: %s\n", index);
error_s("invalid number: %s", index);
break;
}
if (matches < 1) {
error_s("matches cannot be less than 1\n");
error_s("matches cannot be less than 1");
break;
}
}
@ -815,7 +815,7 @@ test:
for (i = 0; i < address.data.set.s; i++) {
matches_found += substute_string(address.data.set.b[i], matches, last_regex, replace, sub_len);
}
output("replaced %ld matches over %ld lines\n", matches_found, address.data.set.s);
output("replaced %ld matches over %ld lines", matches_found, address.data.set.s);
pending_writes = true;
break;
}
@ -865,7 +865,7 @@ test:
printf("%ld\n", line_current + 1);
break;
default:
error_s("unimplemented command\n");
error_s("unimplemented command");
break;
}