init: code du lecteur de stdin

.gitignore

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+/out

Makefile

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+.PHONY: all clean
+
+all: out out/sh
+
+out:
+	mkdir -p -- $@
+
+out/sh: $(wildcard src/*.c)
+	cc -g -Wall -Wextra -Werror -ansi -o $@ $^

src/main.c

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+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+int main() {
+  size_t buffer_size;
+  size_t initial_buffer_size = 64;
+  char *input_buffer;
+  char *initial_buffer_position;
+  unsigned int how_many_characters_to_read;
+
+  while (1) {
+    buffer_size = initial_buffer_size;
+    how_many_characters_to_read = buffer_size + 1;
+    input_buffer = malloc(how_many_characters_to_read);
+    initial_buffer_position = input_buffer;
+
+    printf("shell> ");
+    while (fgets(input_buffer, how_many_characters_to_read, stdin) != NULL &&
+           input_buffer[strlen(input_buffer) - 1] != '\n') {
+      size_t new_buffer_size = buffer_size * 2;
+      if (buffer_size != initial_buffer_size) {
+        how_many_characters_to_read = buffer_size + 1;
+      }
+      input_buffer = realloc(initial_buffer_position, new_buffer_size + 1);
+      initial_buffer_position = input_buffer;
+      input_buffer += buffer_size;
+      buffer_size = new_buffer_size;
+    }
+    input_buffer = initial_buffer_position;
+
+    printf("%s", input_buffer);
+
+    free(input_buffer);
+  }
+}