'

micromake/src/micromake.c

@@ -8,40 +8,112 @@
 #include <stdlib.h>
 
 // Helps to match a string (excludes blanks and special characters)
-int is_char(char c)
+static int is_char(char c)
 {
     return c != '\0' && !isblank(c) && c != ':' && c != '=' && c != '#';
 }
 
+// Returns the next word from buf until buf_len,
+// and the numbers of read characters in *read_chars
+// WARNING allocates the result on the heap
+static char *readWord(char *buf, size_t buf_len, size_t *read_chars)
+{
+    size_t i = 0;
+    size_t str_buf_size = STRING_BUFFER_SIZE;
+    char *str_buf = malloc(sizeof(char) * str_buf_size);
+    while (i < buf_len && is_char(buf[i]))
+    {
+        // Reallocate more space if necessary
+        if (i >= str_buf_size - 1)
+        {
+            str_buf_size += STRING_BUFFER_SIZE;
+            str_buf = realloc(str_buf, str_buf_size);
+            if (str_buf == NULL)
+                errx(2, "Could not realloc");
+        }
+
+        str_buf[i] = buf[i];
+        i++;
+    }
+
+    str_buf[i] = '\0';
+    *read_chars = i;
+
+    return str_buf;
+}
+
+int skip_blanks(char *buf, size_t buf_len)
+{
+    size_t i = 0;
+    while (i < buf_len && isblank(buf[i]))
+        i++;
+    return i;
+}
+
 int main(int argc, char **argv)
 {
+    if (argc < 2)
+        errx(2, "Not enough arguments");
+    if (argc > 2)
+        errx(2, "Not enough arguments");
+
     // Open file
     FILE *stream = fopen(argv[1], "r");
     if (stream == 0)
-        errx(1, "Could not open file");
+        errx(2, "Could not open file");
 
     // Allocate buffer
     size_t buf_size = BUFFER_SIZE;
     char *buf = malloc(sizeof(char) * buf_size);
     if (buf == NULL)
-        errx(1, "Could not allocate more memory");
+        errx(2, "Could not allocate more memory");
 
     // Read
     ssize_t nread;
     while ((nread = getline(&buf, &buf_size, stream)) != -1)
     {
-        int i = 0;
+        size_t u_nread = nread;
+        size_t i = 0;
         // Skip blanks
-        while (i < nread && isblank(buf[i]))
-            i++;
+        i += skip_blanks(buf + i, nread - i);
 
         // Read target name
-        size_t str_buf_size = STRING_BUFFER_SIZE;
-        char *str_buf = malloc(sizeof(char) * str_buf_size);
-        while (is_char(buf[i]))
-        {
-        }
+        size_t skipped_chars = 0;
+        char *rule_name = readWord(buf + i, nread - i, &skipped_chars);
+        if (skipped_chars != 0)
+            printf("%s:", rule_name);
+        i += skipped_chars;
+
+        // Skip until ':'
+        i += skip_blanks(buf + i, nread - i);
+        if (buf[i] != ':')
+            errx(2, "Unexpected character '%c' after rule declaration '%s'",
+                 buf[i], rule_name);
+        i++;
 
         // Read deps
+        while (i < u_nread)
+        {
+            // Skip blanks
+            i += skip_blanks(buf + i, nread - i);
+
+            // Read word
+            size_t skipped_chars = 0;
+            char *dep_name = readWord(buf + i, nread - i, &skipped_chars);
+            if (skipped_chars != 0)
+                printf(" %s", dep_name);
+            free(dep_name);
+            i += skipped_chars;
+
+            if (!is_char(buf[i]) && !isblank(buf[i]) && buf[i] != '\0')
+                errx(2, "Unexpected character '%c'", buf[i]);
+        }
+
+        i++;
+        free(rule_name);
     }
+
+    free(buf);
+    fclose(stream);
+    return 0;
 }