From b702e6e92e5dc5bf272a60e1d5d58ca878928d30 Mon Sep 17 00:00:00 2001 From: Dm1tr1y147 Date: Wed, 8 Jul 2020 18:13:58 +0500 Subject: [PATCH] initial commit --- .gitignore | 5 ++ Makefile | 29 ++++++++ README.md | 0 include/input.h | 25 +++++++ include/keys.h | 15 ++++ include/output.h | 11 +++ include/shell.h | 28 ++++++++ include/utils.h | 14 ++++ src/input.c | 173 +++++++++++++++++++++++++++++++++++++++++++++++ src/keys.c | 114 +++++++++++++++++++++++++++++++ src/main.c | 23 +++++++ src/output.c | 17 +++++ src/shell.c | 156 ++++++++++++++++++++++++++++++++++++++++++ src/utils.c | 33 +++++++++ 14 files changed, 643 insertions(+) create mode 100644 .gitignore create mode 100644 Makefile create mode 100644 README.md create mode 100644 include/input.h create mode 100644 include/keys.h create mode 100644 include/output.h create mode 100644 include/shell.h create mode 100644 include/utils.h create mode 100644 src/input.c create mode 100644 src/keys.c create mode 100644 src/main.c create mode 100644 src/output.c create mode 100644 src/shell.c create mode 100644 src/utils.c diff --git a/.gitignore b/.gitignore new file mode 100644 index 0000000..fa31388 --- /dev/null +++ b/.gitignore @@ -0,0 +1,5 @@ +build/ +.vscode/ +a.out +val/ +tmp* \ No newline at end of file diff --git a/Makefile b/Makefile new file mode 100644 index 0000000..f9fcb25 --- /dev/null +++ b/Makefile @@ -0,0 +1,29 @@ +TARGET_EXEC ?= msh + +BUILD_DIR ?= ./build +SRC_DIRS ?= ./src + +SRCS := $(shell find $(SRC_DIRS) -name *.c) +OBJS := $(SRCS:%=$(BUILD_DIR)/%.o) +DEPS := $(OBJS:.o=.d) + +INC_DIRS := $(shell find $(SRC_DIRS) -type d) +INC_FLAGS := $(addprefix -I,$(INC_DIRS)) + +CPPFLAGS ?= $(INC_FLAGS) -MMD -MP + +$(BUILD_DIR)/$(TARGET_EXEC): $(OBJS) + $(CC) -ggdb3 $(OBJS) -o $@ $(LDFLAGS) + +$(BUILD_DIR)/%.c.o: %.c + $(MKDIR_P) $(dir $@) + $(CC) -ggdb3 $(CPPFLAGS) $(CFLAGS) -c $< -o $@ + +.PHONY: clean + +clean: + $(RM) -r $(BUILD_DIR) + +-include $(DEPS) + +MKDIR_P ?= mkdir -p diff --git a/README.md b/README.md new file mode 100644 index 0000000..e69de29 diff --git a/include/input.h b/include/input.h new file mode 100644 index 0000000..442c6bf --- /dev/null +++ b/include/input.h @@ -0,0 +1,25 @@ +#ifndef _INPUT_H +#define _INPUT_H + +#include +#include +#include + +enum keys { + DELETE_KEY = 1000, + LEFT_KEY, + RIGHT_KEY, + HOME_KEY, + END_KEY, + BACKSPACE_KEY, + ENTER_KEY, + TAB_KEY, + ESCAPE_KEY, + CTRL_C_KEY +}; + +void change_mode(int on); +char *read_line(char **line); +int process_keypress(char c); + +#endif \ No newline at end of file diff --git a/include/keys.h b/include/keys.h new file mode 100644 index 0000000..9e607b7 --- /dev/null +++ b/include/keys.h @@ -0,0 +1,15 @@ +#ifndef _KEYS_H +#define _KEYS_H + +#include + +void delete_key(int pos, int *n, char **line); +void move_left(int *pos); +void move_right(int *pos, int n); +void home_key(int *pos); +void end_key(int *pos, int n); +void backspace_key(int *pos, int *n, char **line); +void new_line(); +void printable_key(int *pos, int *n, char c, char **line); + +#endif \ No newline at end of file diff --git a/include/output.h b/include/output.h new file mode 100644 index 0000000..9c27a44 --- /dev/null +++ b/include/output.h @@ -0,0 +1,11 @@ +#ifndef _OUTPUT_H +#define _OUTPUT_H + +#include +#include +#include + +size_t append_to_buff(char **buff, size_t *buff_size, char *ap, size_t ap_size); +void print_str(char *buff, size_t size); + +#endif \ No newline at end of file diff --git a/include/shell.h b/include/shell.h new file mode 100644 index 0000000..6b2551c --- /dev/null +++ b/include/shell.h @@ -0,0 +1,28 @@ +#ifndef _SHELL_H +#define _SHELL_H + +#include +#include +#include +#include + +#include +#include + +#define BUFF_SIZE 1024 +#define ARG_SIZE 32 + +char *read_line(); +void process_line(char *line, char ***args); +int launch(char **args); +void process_command(); +int execute(char **args); + +void sig_handler(); + +int sh_cd(char **args); +int sh_exit(char **args); + +#define BUILTIN_NUM sizeof(builtin) / sizeof(char *) + +#endif \ No newline at end of file diff --git a/include/utils.h b/include/utils.h new file mode 100644 index 0000000..ed8544c --- /dev/null +++ b/include/utils.h @@ -0,0 +1,14 @@ +#ifndef _UTILS_H +#define _UTILS_H + +#include +#include +#include +#include +#include + +void die(char *s); +void append_to_pos(char **str, int pos, char ch); +void remove_on_pos(char **str, int pos); + +#endif \ No newline at end of file diff --git a/src/input.c b/src/input.c new file mode 100644 index 0000000..e5c0f49 --- /dev/null +++ b/src/input.c @@ -0,0 +1,173 @@ +#include "../include/input.h" +#include "../include/keys.h" + +/** + * @brief Switches console raw mode + * + * @param on + */ +void change_mode(int on) +{ + static struct termios oldt, newt; + + if (on) + { + tcgetattr(STDIN_FILENO, &oldt); + newt = oldt; + newt.c_lflag &= ~(ICANON | ECHO); + tcsetattr(STDIN_FILENO, TCSANOW, &newt); + } + else + tcsetattr(STDIN_FILENO, TCSANOW, &oldt); +} + +/** + * @brief Reads line from user input and puts it into "line" + * + * @param line + * @return char* + */ +char *read_line(char **line) +{ + int c; + int n = 0, pos = 0; + + while (read(STDIN_FILENO, &c, 1)) + { + c = process_keypress(c); + + if (c) + { + switch (c) + { + case DELETE_KEY: + delete_key(pos, &n, line); + break; + + case LEFT_KEY: + move_left(&pos); + break; + + case RIGHT_KEY: + move_right(&pos, n); + break; + + case HOME_KEY: + home_key(&pos); + break; + + case END_KEY: + end_key(&pos, n); + break; + + case BACKSPACE_KEY: + backspace_key(&pos, &n, line); + break; + + case ENTER_KEY: + new_line(); + + return *line; + break; + + case TAB_KEY: + { + // char *buff = malloc(1); + // buff[0] = '\0'; + // size_t buff_size = 1; + + // n += 2; + // append_to_buff(&buff, &buff_size, " ", 2); + // for (int i = 0; i < 2; i++) + // append_to_pos(line, pos, ' '); + // append_to_buff(&buff, &buff_size, "\0337", 2); + // pos += 2; + // append_to_buff(&buff, &buff_size, *line + pos, n - pos); + // append_to_buff(&buff, &buff_size, "\0338", 2); + + // print_str(buff, buff_size); + + // TODO: autocomplete + } + break; + + case ESCAPE_KEY: + break; + + default: + if ((c > 31 && c < 127) || (c > 127 && c < 255)) + printable_key(&pos, &n, (char)c, line); + + break; + } + } + } +} + +/** + * @brief Processes user keypress, filters special characters + * + * @param c + * @return int + */ +int process_keypress(char c) +{ + char seq[3]; + if (c == '\x1b') + { + for (int i = 0; i < 2; i++) + if (read(STDIN_FILENO, &seq[i], 1) == -1) + return ESCAPE_KEY; + if (seq[0] == '[') + { + if (seq[1] >= '0' && seq[1] <= '9') + { + read(STDIN_FILENO, &seq[2], 1); + if (seq[2] == '~') + { + switch (seq[1]) + { + case '3': + return DELETE_KEY; + break; + } + } + } + switch (seq[1]) + { + case 'D': + return LEFT_KEY; + break; + + case 'C': + return RIGHT_KEY; + break; + + case 'H': + return HOME_KEY; + break; + + case 'F': + return END_KEY; + break; + } + } + return ESCAPE_KEY; + } + else if (c == 127) + { + return BACKSPACE_KEY; + } + else if (c == '\n') + { + return ENTER_KEY; + } + else if (c == '\t') + { + return TAB_KEY; + } + else + { + return c; + } +} \ No newline at end of file diff --git a/src/keys.c b/src/keys.c new file mode 100644 index 0000000..9a08cee --- /dev/null +++ b/src/keys.c @@ -0,0 +1,114 @@ +#include "../include/keys.h" +#include "../include/output.h" +#include "../include/utils.h" + +void delete_key(int pos, int *n, char **line) +{ + if (pos < *n) + { + remove_on_pos(line, pos + 1); + (*n)--; + + char *buff = malloc(1); + buff[0] = '\0'; + size_t buff_size = 1; + + append_to_buff(&buff, &buff_size, "\0337", 2); + append_to_buff(&buff, &buff_size, *line + pos, *n - pos); + append_to_buff(&buff, &buff_size, " ", 1); + append_to_buff(&buff, &buff_size, "\0338", 2); + + print_str(buff, buff_size); + } +} + +void move_left(int *pos) +{ + if (*pos > 0) + { + print_str("\033[D", 3); + (*pos)--; + } +} + +void move_right(int *pos, int n) +{ + if (*pos < n) + { + print_str("\033[C", 3); + (*pos)++; + } +} + +void home_key(int *pos) +{ + char *buff = malloc(1); + buff[0] = '\0'; + size_t buff_size = 1; + + for (int i = 0; i < *pos; i++) + append_to_buff(&buff, &buff_size, "\033[D", 3); + + print_str(buff, buff_size); + *pos = 0; +} + +void end_key(int *pos, int n) +{ + char *buff = malloc(1); + buff[0] = '\0'; + size_t buff_size = 1; + + for (int i = 0; i < n - *pos; i++) + append_to_buff(&buff, &buff_size, "\033[C", 3); + + print_str(buff, buff_size); + + *pos = n; +} + +void backspace_key(int *pos, int *n, char **line) +{ + if (*pos > 0) + { + remove_on_pos(line, *pos); + (*n)--; + (*pos)--; + + char *buff = malloc(1); + buff[0] = '\0'; + size_t buff_size = 1; + + append_to_buff(&buff, &buff_size, "\033[D", 3); + append_to_buff(&buff, &buff_size, "\0337", 2); + append_to_buff(&buff, &buff_size, *line + *pos, *n - *pos); + append_to_buff(&buff, &buff_size, " ", 1); + append_to_buff(&buff, &buff_size, "\0338", 2); + + print_str(buff, buff_size); + } +} + +void new_line() +{ + print_str("\n", 1); +} + +void printable_key(int *pos, int *n, char c, char **line) +{ + char *buff = malloc(1); + buff[0] = '\0'; + size_t buff_size = 1; + + (*n)++; + append_to_buff(&buff, &buff_size, &c, 1); + + append_to_pos(line, *pos, c); + + append_to_buff(&buff, &buff_size, "\0337", 2); + (*pos)++; + append_to_buff(&buff, &buff_size, *line + *pos, *n - *pos); + append_to_buff(&buff, &buff_size, "\0338", 2); + + print_str(buff, buff_size); +} \ No newline at end of file diff --git a/src/main.c b/src/main.c new file mode 100644 index 0000000..1831725 --- /dev/null +++ b/src/main.c @@ -0,0 +1,23 @@ +#include + +#include "../include/input.h" +#include "../include/utils.h" +#include "../include/shell.h" + +void exit_shell() +{ + change_mode(0); +} + +int main(int argc, char **argv) +{ + change_mode(1); + signal(SIGINT, SIG_IGN); + + atexit(exit_shell); + + while (1) + { + process_command(); + } +} \ No newline at end of file diff --git a/src/output.c b/src/output.c new file mode 100644 index 0000000..0e555ad --- /dev/null +++ b/src/output.c @@ -0,0 +1,17 @@ +#include "../include/output.h" + +size_t append_to_buff(char **buff, size_t *buff_size, char *ap, size_t ap_size) +{ + *buff = realloc(*buff, *buff_size + ap_size); + memcpy(*buff + *buff_size - 1, ap, ap_size); + + *buff_size += ap_size; + (*buff)[*buff_size - 1] = '\0'; + + return *buff_size; +} + +void print_str(char *buff, size_t size) +{ + write(STDOUT_FILENO, buff, size); +} \ No newline at end of file diff --git a/src/shell.c b/src/shell.c new file mode 100644 index 0000000..11f432f --- /dev/null +++ b/src/shell.c @@ -0,0 +1,156 @@ +#include "../include/shell.h" +#include "../include/input.h" +#include "../include/output.h" + +/* Global definitions */ +char *builtin[] = { + "cd", + "exit"}; + +int (*builtin_func[])(char **) = { + &sh_cd, + &sh_exit}; + +/** + * @brief Function for main loop. It prints prompt, reads user's input and executes it + */ +void process_command() +{ + char **args; + int status; + + do + { + char *line = malloc(1); + line[0] = '\0'; + + if (getuid() == 0) + print_str("# ", 2); + else + print_str("> ", 2); + + line = read_line(&line); + + process_line(line, &args); + status = execute(args); + + free(line); + free(args); + } while (status); +} + +/** + * @brief Extracts command and its arguments from line + * + * @param line + * @param args + */ +void process_line(char *line, char ***args) +{ + int buff_size = ARG_SIZE, pos = 0; + *args = malloc(buff_size * sizeof(char *)); + char *tok, *rest = strdup(line); + + while ((tok = strtok_r(rest, " \t", &rest)) != NULL) + { + (*args)[pos] = tok; + pos++; + + if (pos > buff_size) + { + buff_size += ARG_SIZE; + *args = realloc(*args, buff_size * sizeof(char *)); + if (*args == NULL) + { + fprintf(stderr, "myshell: allocation error"); + exit(EXIT_FAILURE); + } + } + } + + (*args)[pos] = NULL; +} + +/** + * @brief Executes either builtin or system command + * + * @param args + * @return int + */ +int execute(char **args) +{ + if (args[0] == NULL) + return 1; + + for (int i = 0; i < BUILTIN_NUM; i++) + if (strcmp(args[0], builtin[i]) == 0) + return (*builtin_func[i])(args); + + return launch(args); +} + +/** + * @brief Launches separate process and executes specified command + * + * @param args + * @return int + */ +int launch(char **args) +{ + pid_t pid, wpid; + int status; + + pid = fork(); + + if (pid == 0) + { + change_mode(0); + signal(SIGINT, SIG_DFL); + + if (execvp(args[0], args) < 0) + { + perror("myshell"); + } + + exit(EXIT_FAILURE); + } + else if (pid < 0) + { + perror("myshell"); + } + else + do + wpid = waitpid(pid, &status, WUNTRACED); + while (!WIFEXITED(status) && !WIFSIGNALED(status)); + + change_mode(1); + + return status; +} + +/** + * @brief Shell builtin command. Changes current working directory + * + * @param args + * @return int + */ +int sh_cd(char **args) +{ + if (args[1] == NULL) + fprintf(stderr, "myshell: expected arguments for \"cd\"\n"); + else if (chdir(args[1]) < 0) + perror("myshell"); + + return 1; +} + +/** + * @brief Shell builtin command. Exits shell + * + * @param args + * @return int + */ +int sh_exit(char **args) +{ + exit(0); +} \ No newline at end of file diff --git a/src/utils.c b/src/utils.c new file mode 100644 index 0000000..9081e5d --- /dev/null +++ b/src/utils.c @@ -0,0 +1,33 @@ +#include "../include/utils.h" + +void die(char *s) +{ + perror(s); + exit(1); +} + +void append_to_pos(char **str, int pos, char ch) +{ + size_t len = strlen(*str); + + *str = realloc(*str, len + 2); + + for (int i = len; i >= pos; i--) + { + (*str)[i + 1] = (*str)[i]; + } + (*str)[pos] = ch; + (*str)[len + 1] = '\0'; +} + +void remove_on_pos(char **str, int pos) +{ + size_t len = strlen(*str); + + for (int i = pos - 1; i <= len; i++) + { + (*str)[i] = (*str)[i + 1]; + } + (*str)[len] = '\0'; + *str = realloc(*str, len); +} \ No newline at end of file