put a possibly better preproc_readr.c in attic

attic/preproc_readr.c

@@ -0,0 +1,115 @@
+#include <R.h>
+#include <Rinternals.h>
+#include <Rdefines.h>
+#include <ctype.h>
+#include "tools.h"
+
+void rd_convert_line(char s[], char t[]) {
+  int i = 0;
+  int j = 0;
+  int in_quotes = 0;
+  int is_quote = 0;
+  char old_quote = 0;
+  int done = 0;
+
+  while(!done) {
+    /* got string delim: copy + take a break */
+    if (s[i] == 0) {
+      t[j] = 0; i++; j++;
+      break;
+    }
+
+    if (in_quotes) {
+      /* in quote, we copy all chars, except if we find the exakt old quote char from the start */
+      /* in that case we copy " to t and leave quote mode */
+      if (s[i] == old_quote) {
+        t[j] = '"'; i++; j++;
+        in_quotes = 0;
+      } else if (s[i] == '\\') {
+        if (s[i+1] == 'n') {
+          t[j] = '\n'; i+=2; j+=1;
+        } else if (s[i+1] == '\'' && old_quote == '\'') {
+          t[j] = '\''; i+=2; j+=1;
+        } else if (s[i+1] == '"' && old_quote == '\'') {
+          t[j] = '\\'; t[j+1] = '"';  i+=2; j+=2;
+        } else if (s[i+1] == '"' && old_quote == '"') {
+          t[j] = '\\'; t[j+1] = '"';  i+=2; j+=2;
+        } else {
+          i += 1;
+        }
+      } else {
+        t[j] = s[i]; i++; j++;
+      }
+    } else {
+      switch(s[i]) {
+        case '%': /* found comment char: set linebreak in t and stop copying */
+          t[j] = '\n'; t[j+1] = 0; done = 1; break;
+        case '\'':; /* found quote: copy " to t, go to quoted mode and store old quote */
+        case '"':
+          t[j] = '"'; old_quote = s[i]; in_quotes = 1; i++; j++; break;
+        case ' ': /* got space: remove the crap */
+          i++; break;
+        case '?': /* got ?: copy NA */
+         t[j++] = 'N'; t[j++] = 'A'; i++; break;
+        default: /*copy slot */
+          t[j] = s[i]; i++; j++; break;
+      }
+    }
+  }
+}
+
+/* throw away line if it
+ * - is empty
+ * - exactly starts with comment char '%'
+*/
+SEXP c_rd_preproc(SEXP s_path_in, SEXP s_path_out, SEXP s_data_sect_index) {
+
+  FILE* handle_in;
+  FILE* handle_out;
+  const char* path_in = CHAR(asChar(s_path_in));
+  const char* path_out = CHAR(asChar(s_path_out));
+  int data_sect_index = asInteger(s_data_sect_index);
+  /* char line_buf_1[MAX_LINE_LEN]; */
+  /* char line_buf_2[MAX_LINE_LEN]; */
+  char* line_buf_1;
+  char* line_buf_2;
+  char* line_p;
+  int data_sect_reached = 0;
+  int gl_line_bytes = 100000;
+  int gl_bytes_read;
+
+  handle_in = fopen(path_in, "r");
+  handle_out = fopen(path_out, "w");
+
+  /* FIXME: can we skip these lines faster? */
+  for (int i = 0; i<data_sect_index; i++) {
+    line_buf_1 = (char *) malloc (gl_line_bytes + 1);
+    gl_bytes_read = getline(&line_buf_1, &gl_line_bytes, handle_in);
+    Rprintf("%i\n", i);
+    Rprintf("%s\n", line_buf_1);
+    if (gl_bytes_read == -1)
+      error("error in getline1!");
+    free(line_buf_1);
+    /* fgets(line_buf_1, sizeof line_buf_1, handle_in); */
+  }
+  while (fgets(line_buf_1, sizeof line_buf_1, handle_in)) {
+    line_buf_1 = (char *) malloc (gl_line_bytes + 1);
+    gl_bytes_read = getline(&line_buf_1, &gl_line_bytes, handle_in);
+    Rprintf("%s\n", line_buf_1);
+    if (gl_bytes_read == -1)
+      error("error in getline2!");
+    line_buf_2 = (char *) malloc (gl_bytes_read + 1);
+    rd_convert_line(line_buf_1, line_buf_2);
+    if (!is_empty(line_buf_2))
+      fputs(line_buf_2, handle_out);
+    free(line_buf_1);
+    free(line_buf_2);
+  }
+  fclose(handle_in);
+  fclose(handle_out);
+  return R_NilValue;
+}
+
+
+
+