Added xargs utility, Added -std=c99 flag

9 files changed, 253 insertions, 17 deletions

diff --git a/.gitignore b/.gitignore
index 11269e8..09b23ad 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,3 +1,4 @@
 a.out
 *.o
 bin/*
+tags
diff --git a/Makefile b/Makefile
index 450a5f4..1421b3f 100644
--- a/Makefile
+++ b/Makefile
@@ -2,11 +2,11 @@ BINDIR = bin
 SRCDIR = src
 
 CC = gcc
-CCFLAGS = -Wall -Wextra -Wpedantic
+CCFLAGS = -std=c99 -Wall -Wextra -Wpedantic -Wno-implicit-fallthrough
 
 all: prebuild $(BINDIR)/basename $(BINDIR)/chown $(BINDIR)/cut $(BINDIR)/head \
 		$(BINDIR)/mkdir $(BINDIR)/mv $(BINDIR)/rm $(BINDIR)/seq \
-		$(BINDIR)/shuf $(BINDIR)/tee $(BINDIR)/tr \
+		$(BINDIR)/shuf $(BINDIR)/tee $(BINDIR)/tr $(BINDIR)/xargs \
 		$(BINDIR)/shuf_trand
 
 prebuild:
@@ -45,6 +45,9 @@ $(BINDIR)/tee: $(SRCDIR)/tee.c
 $(BINDIR)/tr: $(SRCDIR)/tr.c
 	$(CC) $(CCFLAGS) -o $@ $^
 
+$(BINDIR)/xargs: $(SRCDIR)/xargs.c
+	$(CC) $(CCFLAGS) -o $@ $^
+
 #### shuf using trand
 TRAND_PATH = trand
 
diff --git a/README.md b/README.md
index b287118..308cfe0 100644
--- a/README.md
+++ b/README.md
@@ -16,11 +16,12 @@ Rewrite of some core utilities for educational purposes.
 ## Pending
 
 | Name       | Description |
-|------------|-----------------------------------------------------------------|
-| `cut`      | remove sections from each line of files                         |
-| `uniq`     | report or omit repeated lines |
-| `tr`       | translate or delete characters |
-| `chown`    | change file owner and group |
+|------------|----------------------------------------------------------------- |
+| `cut`      | remove sections from each line of files                          |
+| `uniq`     | report or omit repeated lines                                    |
+| `tr`       | translate or delete characters                                   |
+| `chown`    | change file owner and group                                      |
+| `xargs`    | construct argument lists and invoke utility                      |
 
 ## TODO
 
diff --git a/src/basename.c b/src/basename.c
index 83f3b8f..3e58cb6 100644
--- a/src/basename.c
+++ b/src/basename.c
@@ -1,3 +1,4 @@
+#define _POSIX_C_SOURCE 2
 #include <unistd.h>
 #include <stdio.h>
 #include <stdlib.h>
diff --git a/src/cut.c b/src/cut.c
index 2a7990d..38e1cd8 100644
--- a/src/cut.c
+++ b/src/cut.c
@@ -46,18 +46,17 @@ int		parse_uint(char *s, char **endptr)
 
 int 	main(int argc, char **argv)
 {
-	int					option;
-	int	list_start = LIST_VALUE_INFINITY;
-	int	list_end   = LIST_VALUE_INFINITY;
-	t_list_type			list_type  = LIST_UNDEFINED;
-	wchar_t				delimiter  = '\t';
-	bool				print_only_delimiter = false;
-	char				line_delimiter = '\n';
+	int         option;
+	int         list_start           = LIST_VALUE_INFINITY;
+	int         list_end             = LIST_VALUE_INFINITY;
+	t_list_type list_type            = LIST_UNDEFINED;
+	wchar_t     delimiter            = '\t';
+	bool        print_only_delimiter = false;
+	char        line_delimiter       = '\n';
 
 	g_name = argv[0];
 	while ((option = getopt(argc, argv, "b:c:d:f:sz")) > 0)
 	{
-
 		switch (option)
 		{
 			case 'b':
@@ -188,6 +187,8 @@ int 	main(int argc, char **argv)
 						counter++;
 					}
 					break;
+				default:
+					fatal_errno();
 			}
 			putchar('\n');
 		}
diff --git a/src/head.c b/src/head.c
index f2201b5..98e3b57 100644
--- a/src/head.c
+++ b/src/head.c
@@ -1,3 +1,4 @@
+#define _POSIX_C_SOURCE 200809L
 #include <unistd.h>
 #include <stdio.h>
 #include <stdlib.h>
diff --git a/src/seq.c b/src/seq.c
index 8307fc4..20d65cd 100644
--- a/src/seq.c
+++ b/src/seq.c
@@ -109,13 +109,13 @@ int				main(int argc, char **argv)
 	{
 		int precision = MAX(first.precision, increment.precision);
 		if (!padding)
-			printf("%.*llf", precision, first.value);
+			printf("%.*Lf", precision, first.value);
 		else
 		{
 			int width = MAX(last.integer_len, first.integer_len);
 			if (precision != 0)
 				width += precision + 1;
-			printf("%0*.*llf", width, precision, first.value);
+			printf("%0*.*Lf", width, precision, first.value);
 		}
 		first.value += increment.value;
 		if (increment.value > 0 ? (first.value <= last.value) : (first.value >= last.value))
diff --git a/src/xargs.c b/src/xargs.c
new file mode 100644
index 0000000..9c2a5e6
--- /dev/null
+++ b/src/xargs.c
@@ -0,0 +1,228 @@
+#define _POSIX_C_SOURCE 200809L
+#define _DEFAULT_SOURCE 1
+
+#include <unistd.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <ctype.h>
+#include <stdbool.h>
+#include <errno.h>
+#include <stdarg.h>
+#include <string.h>
+#include <sys/wait.h>
+
+static char   *g_eofstr    = NULL;
+static char   *g_replstr   = NULL;
+static size_t g_line_count = -1;
+static size_t g_arg_count  = -1;
+static bool   g_prompt     = false;
+static size_t g_size       = -1;
+static bool   g_trace      = false;
+static bool   g_terminate  = false;
+
+static char   *g_name      = "xargs";
+
+void die(const char *fmt, ...)
+{
+	va_list ap;
+
+	va_start(ap, fmt);
+	fprintf(stderr, "%s: ", g_name);
+	vfprintf(stderr, fmt, ap);
+	fputc('\n', stderr);
+	va_end(ap);
+	exit(1);
+}
+
+void *xmalloc(size_t size)
+{
+	void *ret = malloc(size);
+	if (ret == NULL)
+		die(strerror(errno));
+	return ret;
+}
+
+char *xstrdup(const char *src)
+{
+	char *ret = strdup(src);
+	if (ret == NULL)
+		die(strerror(errno));
+	return ret;
+}
+
+size_t parse_uint(const char *optarg)
+{
+	unsigned long n;
+	char          *end;
+
+	errno = 0;
+	n = strtoul(optarg, &end, 10);
+	if (!isdigit(*optarg) || errno != 0 || *end != '\0')
+		die("invalid number \"%s\"", optarg);
+	return n;
+}
+
+size_t args_len(char **args)
+{
+	size_t	len;
+	for (len = 0; args[len] != NULL; len++);
+	return len;
+}
+
+void args_free(char **args)
+{
+	for (size_t i = 0; args[i] != NULL; i++)
+		free(args[i]);
+	free(args);
+}
+
+char **args_cpy(char **dst, char **src)
+{
+	size_t i;
+
+	for (i = 0; src[i] != NULL; i++)
+		dst[i] = xstrdup(src[i]);
+	dst[i] = NULL;
+	return dst;
+}
+
+char **args_dup(char **src)
+{
+	char **ret = xmalloc((args_len(src) + 1) * sizeof(char*));
+	return args_cpy(ret, src);
+}
+
+int main(int argc, char **argv)
+{
+	int option;
+
+	while ((option = getopt(argc, argv, "E:I:L:n:ps:tx")) > 0)
+	{
+		switch (option)
+		{
+			case 'E': g_eofstr     = optarg;             break;
+			case 'I': g_replstr    = optarg;             break;
+			case 'L': g_line_count = parse_uint(optarg); break;
+			case 'n': g_arg_count  = parse_uint(optarg); break;
+			case 'p': g_prompt     = true;               break;
+			case 's': g_size       = parse_uint(optarg); break;
+			case 't': g_trace      = true;               break;
+			case 'x': g_terminate  = true;               break;
+		}
+	}
+	if (g_line_count == 0)
+		die("value 0 for -L option should be >= 1");
+	if (g_arg_count == 0)
+		die("value 0 for -n option should be >= 1");
+	if (g_prompt)
+		g_trace = true;
+
+	char *cmd = optind != argc ? argv[optind] : "echo";
+	char **args_prefix;
+	if (optind == argc || optind + 1 == argc)
+	{
+		args_prefix = xmalloc(2 * sizeof(char*));
+		args_prefix[0] = cmd;
+		args_prefix[1] = NULL;
+	}
+	else
+	{
+		size_t len = argc - optind;
+		args_prefix = xmalloc((len + 1) * sizeof(char*));
+		size_t i;
+		for (i = 0; i < len; i++)
+			args_prefix[i] = argv[optind + i];
+		args_prefix[len] = NULL;
+	}
+
+	size_t len;
+	bool eof = false;
+	size_t command_count = 0;
+	while (!eof)
+	{
+		char   **args = args_dup(args_prefix);
+		char   *line = NULL;
+		size_t line_size = 0;
+		size_t count = 0;
+
+		while (getline(&line, &line_size, stdin) > 0)
+		{
+			// removing newline
+			char *last = line + strlen(line) - 1;
+			if (*last == '\n')
+				*last = '\0';
+			// trim blank characters
+			while (isblank(*line))
+				memmove(line, line + 1, strlen(line));
+			len = strlen(line);
+			while (len > 0 && isblank(line[len - 1]))
+			{
+				line[len - 1] = '\0';
+				len--;
+			}
+			// skipping blank lines
+			if (*line == '\0')
+				continue;
+			// stopping if eof string encountered
+			if (g_eofstr != NULL && strcmp(g_eofstr, line) == 0)
+			{
+				eof = true;
+				break;
+			}
+			// add line to arguments
+			len = args_len(args);
+			char **new_args = xmalloc((len + 2) * sizeof(char*));
+			args_cpy(new_args, args);
+			new_args[len] = xstrdup(line);
+			new_args[len + 2] = NULL;
+			/* args_free(args); */
+			args = new_args;
+			count++;
+			if ((g_line_count != (size_t)-1 && count >= g_line_count) ||
+				(g_arg_count != (size_t)-1  && count >= g_arg_count))
+				break;
+		}
+		if (feof(stdin))
+			eof = true;
+		if (eof && command_count != 0 && !g_prompt)
+			break;
+		command_count++;
+
+		pid_t child_pid;
+		child_pid = fork();
+		switch (child_pid)
+		{
+			case -1:
+				die(strerror(errno));
+				break;
+			case 0:
+				if (g_trace)
+					for (size_t i = 0; args[i] != NULL; i++)
+					{
+						fputs(args[i], stderr);
+						if (args[i + 1] != NULL)
+							fputc(' ', stderr);
+					}
+				bool confirmation = true;
+				if (g_prompt)
+				{
+					FILE *tty_file = fopen("/dev/tty", "r");
+					if (tty_file == NULL)
+						die("Couldn't open tty file");
+					fputs(" ?...", stderr);
+					int c = fgetc(tty_file);
+					confirmation = c == 'y' || c == 'Y';
+				}
+				else if (g_trace)
+					fputc('\n', stderr);
+				if (!confirmation)
+					exit(0);
+				execvp(cmd, args);
+				die(strerror(errno));
+		}
+		waitpid(child_pid, &child_pid, 0);
+		if (WEXITSTATUS(child_pid) == 255)
+			break;
+	}
+	return 0;
+}
diff --git a/trand b/trand
-Subproject 994744a3edc74c88271ffe57958a08b70f9f507
+Subproject 638f21e4a3f7dd04d33a147f54b97046800ba1f