pgm 22.9, merge parts files, WIP

Author: twcamper

.gitignore

@@ -173,3 +173,4 @@ spec/parts-list-io-spec
 22/part-structs-io-profiler
 22/parts-array-io-profiler
 22/parts-list-io-profiler
+22/22.9-merge-parts

22/22.9-merge-parts.c

@@ -0,0 +1,134 @@
+#if defined(__linux__) || defined(__linux) || defined(__gnu_linux__)
+#include <sys/types.h>  /* for off_t */
+#endif
+#include <stdio.h>
+#include <sys/stat.h>
+#include "error.h"
+#include "part-type.h"
+
+int main(int argc, char *argv[])
+{
+  if (argc != 4)
+    invocation_error(argv[0], "[input file 1] [input file 2] [output file]"); 
+
+  char *larger_filename, *smaller_filename, *output_filename = argv[3];
+  struct stat file1_stat, file2_stat;
+  off_t record_size = (off_t)get_part_record_size();
+  off_t smaller_size;
+  size_t larger_count, smaller_count;
+
+  if (stat(argv[1], &file1_stat) != 0)
+    exit_error(errno, argv[0], argv[1]);
+
+  if (file1_stat.st_size % record_size)
+    fprintf(stderr, "Corrupt file '%s': size must be multiple of %ld\n",
+        argv[1],
+        (size_t)record_size);
+
+  if (stat(argv[2], &file2_stat) != 0)
+    exit_error(errno, argv[0], argv[2]);
+
+  if (file2_stat.st_size % record_size)
+    fprintf(stderr, "Corrupt file '%s': size must be multiple of %ld\n",
+        argv[2],
+        (size_t)record_size);
+
+  if (file1_stat.st_size > file2_stat.st_size) {
+    larger_filename = argv[1];
+    smaller_filename = argv[2];
+    smaller_size = file2_stat.st_size;
+    larger_count = file1_stat.st_size / record_size;
+    smaller_count = file2_stat.st_size / record_size;
+  } else {
+    larger_filename = argv[2];
+    smaller_filename = argv[1];
+    smaller_size = file1_stat.st_size;
+    larger_count = file2_stat.st_size / record_size;
+    smaller_count = file1_stat.st_size / record_size;
+  }
+
+  size_t combined_size = (size_t) file1_stat.st_size + file2_stat.st_size;
+  Part merge_buffer = (Part)malloc(combined_size);
+  if (!merge_buffer)
+    memory_error(__FILE__, __LINE__, __func__);
+
+  Part other_buffer = malloc(smaller_size);
+  if (!other_buffer)
+    memory_error(__FILE__, __LINE__, __func__);
+
+  FILE *larger_stream, *smaller_stream;
+
+  if ((larger_stream = fopen(larger_filename, "rb")) == NULL) {
+    exit_error(errno,argv[0], larger_filename);
+  }
+
+  if ((smaller_stream = fopen(smaller_filename, "rb")) == NULL) {
+    if (fclose(larger_stream) == EOF)
+      print_error(errno, __FILE__, larger_filename);
+    exit_error(errno,argv[0], smaller_filename);
+  }
+
+  if (fread(merge_buffer, record_size, larger_count, larger_stream) < larger_count) {
+    print_error(errno, argv[0], larger_filename);
+    if (fclose(larger_stream) == EOF)
+      print_error(errno, __FILE__, larger_filename);
+    if (fclose(smaller_stream) == EOF)
+      print_error(errno, __FILE__, smaller_filename);
+    exit(EXIT_FAILURE);
+  }
+  if (fread(other_buffer, record_size, smaller_count, smaller_stream) < smaller_count) {
+    print_error(errno, argv[0], smaller_filename);
+    if (fclose(larger_stream) == EOF)
+      print_error(errno, __FILE__, larger_filename);
+    if (fclose(smaller_stream) == EOF)
+      print_error(errno, __FILE__, smaller_filename);
+    exit(EXIT_FAILURE);
+  }
+  if (fclose(larger_stream) == EOF)
+    print_error(errno, __FILE__, larger_filename);
+  if (fclose(smaller_stream) == EOF)
+    exit_error(errno, __FILE__, smaller_filename);
+
+
+  for (size_t s = 0; s < smaller_count; s++) {
+    for (size_t l = 0; l < larger_count; l++) {
+      if ((merge_buffer + l)->number == (other_buffer + s)->number) {
+        if (strcmp((merge_buffer + l)->name, (other_buffer + s)->name) != 0) {
+          fprintf(stderr, "Part #%d: name conflict\n", (merge_buffer + l)->number);
+          continue;
+        }
+        if (!set_part_on_hand((merge_buffer + l), (other_buffer + s)->on_hand)) {
+          fprintf(stderr, "Invalid new quantity on hand for Part #%d\n", (merge_buffer + l)->number);
+          continue;
+        }
+      }
+    }
+  }
+
+  /*
+   * for each record in the smaller
+   *   check each part number in the larger until:
+   *      same number is found:
+   *        if name values differ
+   *          report to stderr
+   *          continue
+   *        combine in stock values
+   *        if the new value is invalid
+   *          report to stderr
+   *          continue
+   *      larger part number is found:
+   *        increment "added" counter
+   *        shift all subsequent elements in the larger buffer
+   *        copy record from smaller into the hole
+   *      we reach the end without finding a larger part number
+   *        increment "added" counter
+   *        copy record from smaller at end
+   *
+   * open the output file
+   * fwrite the output buffer
+   * close the output file
+   */
+
+
+  return 0;
+}