updated for checking, not much progress

newfiles/diff_02.c

@@ -0,0 +1,175 @@
+//
+//  diff_02.c
+//  diff
+//
+//  Created by William McCarthy on 4/29/19.
+//  Copyright © 2019 William McCarthy. All rights reserved.
+//
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#define ARGC_ERROR 1
+#define TOOMANYFILES_ERROR 2
+#define CONFLICTING_OUTPUT_OPTIONS 3
+
+#define MAXSTRINGS 1024
+#define MAXPARAS 4096
+
+#define HASHLEN 200
+
+#include "para.h"
+#include "util.h"
+
+
+void version(void) {
+  printf("\n\n\ndiff (CSUF diffutils) 1.0.0\n");
+  printf("Copyright (C) 2014 CSUF\n");
+  printf("This program comes with NO WARRANTY, to the extent permitted by law.\n");
+  printf("You may redistribute copies of this program\n");
+  printf("under the terms of the GNU General Public License.\n");
+  printf("For more information about these matters, see the file named COPYING.\n");
+  printf("Written by William McCarthy, Tony Stark, and Dr. Steven Strange\n");
+}
+
+void todo_list(void) {
+  printf("\n\n\nTODO: check line by line in a paragraph, using '|' for differences");
+  printf("\nTODO: this starter code does not yet handle printing all of fin1's paragraphs.");
+  printf("\nTODO: handle the rest of diff's options\n");
+}
+
+char buf[BUFLEN];
+char *strings1[MAXSTRINGS], *strings2[MAXSTRINGS];
+int showversion = 0, showbrief = 0, ignorecase = 0, report_identical = 0, showsidebyside = 0;
+int showleftcolumn = 0, showunified = 0, showcontext = 0, suppresscommon = 0, diffnormal = 0;
+
+int count1 = 0, count2 = 0;
+
+
+void loadfiles(const char* filename1, const char* filename2) {
+  memset(buf, 0, sizeof(buf));
+  memset(strings1, 0, sizeof(strings1));
+  memset(strings2, 0, sizeof(strings2));
+
+  FILE *fin1 = openfile(filename1, "r");
+  FILE *fin2 = openfile(filename2, "r");
+
+  while (!feof(fin1) && fgets(buf, BUFLEN, fin1) != NULL) { strings1[count1++] = strdup(buf); }  fclose(fin1);
+  while (!feof(fin2) && fgets(buf, BUFLEN, fin2) != NULL) { strings2[count2++] = strdup(buf); }  fclose(fin2);
+}
+
+void print_option(const char* name, int value) { printf("%17s: %s\n", name, yesorno(value)); }
+
+void diff_output_conflict_error(void) {
+  fprintf(stderr, "diff: conflicting output style options\n");
+  fprintf(stderr, "diff: Try `diff --help' for more information.)\n");
+  exit(CONFLICTING_OUTPUT_OPTIONS);
+}
+
+void setoption(const char* arg, const char* s, const char* t, int* value) {
+  if ((strcmp(arg, s) == 0) || ((t != NULL && strcmp(arg, t) == 0))) {
+    *value = 1;
+  }
+}
+
+void showoptions(const char* file1, const char* file2) {
+  printf("diff options...\n");
+  print_option("diffnormal", diffnormal);
+  print_option("show_version", showversion);
+  print_option("show_brief", showbrief);
+  print_option("ignorecase", ignorecase);
+  print_option("report_identical", report_identical);
+  print_option("show_sidebyside", showsidebyside);
+  print_option("show_leftcolumn", showleftcolumn);
+  print_option("suppresscommon", suppresscommon);
+  print_option("showcontext", showcontext);
+  print_option("show_unified", showunified);
+
+  printf("file1: %s,  file2: %s\n\n\n", file1, file2);
+
+  printline();
+}
+
+void init_options_files(int argc, const char* argv[]) {
+  int cnt = 0;
+  const char* files[2] = { NULL, NULL };
+
+  while (argc-- > 0) {
+    const char* arg = *argv;
+    setoption(arg, "-v",       "--version",                  &showversion);
+    setoption(arg, "-q",       "--brief",                    &showbrief);
+    setoption(arg, "-i",       "--ignore-case",              &ignorecase);
+    setoption(arg, "-s",       "--report-identical-files",   &report_identical);
+    setoption(arg, "--normal", NULL,                         &diffnormal);
+    setoption(arg, "-y",       "--side-by-side",             &showsidebyside);
+    setoption(arg, "--left-column", NULL,                    &showleftcolumn);
+    setoption(arg, "--suppress-common-lines", NULL,          &suppresscommon);
+    setoption(arg, "-c",       "--context",                  &showcontext);
+    setoption(arg, "-u",       "showunified",                &showunified);
+    if (arg[0] != '-') {
+      if (cnt == 2) {
+        fprintf(stderr, "apologies, this version of diff only handles two files\n");
+        fprintf(stderr, "Usage: ./diff [options] file1 file2\n");
+        exit(TOOMANYFILES_ERROR);
+      } else { files[cnt++] = arg; }
+    }
+    ++argv;   // DEBUG only;  move increment up to top of switch at release
+  }
+
+  if (!showcontext && !showunified && !showsidebyside && !showleftcolumn) {
+    diffnormal = 1;
+  }
+
+  if (showversion) { version();  exit(0); }
+
+  if (((showsidebyside || showleftcolumn) && (diffnormal || showcontext || showunified)) ||
+      (showcontext && showunified) || (diffnormal && (showcontext || showunified))) {
+
+    diff_output_conflict_error();
+  }
+
+//  showoptions(files[0], files[1]);
+  loadfiles(files[0], files[1]);
+}
+
+int main(int argc, const char * argv[]) {
+  init_options_files(--argc, ++argv);
+
+//  para_printfile(strings1, count1, printleft);
+//  para_printfile(strings2, count2, printright);
+
+  para* p = para_first(strings1, count1);
+  para* q = para_first(strings2, count2);
+  int foundmatch = 0;
+
+  para* qlast = q;
+  while (p != NULL) {
+    qlast = q;
+    foundmatch = 0;
+    while (q != NULL && (foundmatch = para_equal(p, q)) == 0) {
+      q = para_next(q);
+    }
+    q = qlast;
+
+    if (foundmatch) {
+      while ((foundmatch = para_equal(p, q)) == 0) {
+        para_print(q, printright);
+        q = para_next(q);
+        qlast = q;
+      }
+      para_print(q, printboth);
+      p = para_next(p);
+      q = para_next(q);
+    } else {
+      para_print(p, printleft);
+      p = para_next(p);
+    }
+  }
+  while (q != NULL) {
+    para_print(q, printright);
+    q = para_next(q);
+  }
+
+  return 0;
+}

newfiles/left.txt

@@ -0,0 +1,25 @@
+This part of the
+document has stayed the
+sme from version to
+version. It shouldn't
+be shown if it doesn't
+change. Otherwise, that
+would not be helping to
+compress the size of the
+changes.
+
+This paragraph contains
+text that is outdated.
+It will be deleted in the
+near future.
+
+It is important to spell
+check this dokument. On
+the other hand, a
+misspelled word isn't
+the end of the world.
+Nothing in the rest of
+this paragraph needs to
+be changed. Things can
+be added after it.
+

newfiles/para.c

@@ -0,0 +1,85 @@
+//
+//  para.c
+//  diff
+//
+//  Created by William McCarthy on 5/9/19.
+//  Copyright © 2019 William McCarthy. All rights reserved.
+//
+
+#include <stdlib.h>
+#include <string.h>
+#include "para.h"
+#include "util.h"
+
+#define BUFLEN 256
+
+
+para* para_make(char* base[], int filesize, int start, int stop) {
+  para* p = (para*) malloc(sizeof(para));
+  p->base = base;
+  p->filesize = filesize;
+  p->start = start;
+  p->stop = stop;
+  p->firstline = (p == NULL || start < 0) ? NULL : p->base[start];
+  p->secondline = (p == NULL || start < 0 || filesize < 2) ? NULL : p->base[start + 1];
+  
+  return p;
+}
+
+para* para_first(char* base[], int size) {
+  para* p = para_make(base, size, 0, -1);
+  return para_next(p);
+}
+
+void para_destroy(para* p) { free(p); }
+
+para* para_next(para* p) {
+  if (p == NULL || p->stop == p->filesize) { return NULL; }
+  
+  int i;
+  para* pnew = para_make(p->base, p->filesize, p->stop + 1, p->stop + 1);
+  for (i = pnew->start; i < p->filesize && strcmp(p->base[i], "\n") != 0; ++i) { }
+  pnew->stop = i;
+  
+  if (pnew->start >= p->filesize) {
+    free(pnew);
+    pnew = NULL;
+  }
+  return pnew;
+}
+size_t para_filesize(para* p) { return p == NULL ? 0 : p->filesize; }
+
+size_t para_size(para* p) { return p == NULL || p->stop < p->start ? 0 : p->stop - p->start + 1; }
+
+char** para_base(para* p) { return p->base; }
+
+char* para_info(para* p) {
+  static char buf[BUFLEN];   // static for a reason
+  snprintf(buf, sizeof(buf), "base: %p, filesize: %d, start: %d, stop: %d\n",
+           p->base, p->filesize, p->start, p->stop);
+  return buf;  // buf MUST be static
+}
+
+int para_equal(para* p, para* q) {
+  if (p == NULL || q == NULL) { return 0; }
+  if (para_size(p) != para_size(q)) { return 0; }
+  if (p->start >= p->filesize || q->start >= q->filesize) { return 0; }
+  int i = p->start, j = q->start, equal = 0;
+  while ((equal = strcmp(p->base[i], q->base[i])) == 0) { ++i; ++j; }
+  return 1;
+}
+
+void para_print(para* p, void (*fp)(const char*)) {
+  if (p == NULL) { return; }
+  for (int i = p->start; i <= p->stop && i != p->filesize; ++i) { fp(p->base[i]); }
+}
+
+void para_printfile(char* base[], int count, void (*fp)(const char*)) {
+  para* p = para_first(base, count);
+  while (p != NULL) {
+    para_print(p, fp);
+    p = para_next(p);
+  }
+  printline();
+}
+

newfiles/para.h

@@ -0,0 +1,36 @@
+//
+//  para.h
+//  diff
+//
+//  Created by William McCarthy on 5/9/19.
+//  Copyright © 2019 William McCarthy. All rights reserved.
+//
+
+#ifndef para_h
+#define para_h
+
+#include <stdio.h>
+
+typedef struct para para;
+struct para {
+  char** base;
+  int filesize;
+  int start;
+  int stop;
+  char* firstline;   // DEBUG only
+  char* secondline;
+};
+
+para* para_make(char* base[], int size, int start, int stop);
+para* para_first(char* base[], int size);
+para* para_next(para* p);
+size_t para_filesize(para* p);
+size_t para_size(para* p);
+char** para_base(para* p);
+char* para_info(para* p);
+int   para_equal(para* p, para* q);
+void para_print(para* p, void (*fp)(const char*));
+void para_printfile(char* base[], int count, void (*fp)(const char*));
+
+
+#endif /* para_h */

newfiles/right.txt

@@ -0,0 +1,31 @@
+This is an important
+notice! It should
+therefore be located at
+the beginning of this
+document!
+
+This part of the
+document has stayed the
+sme from version to
+version. It shouldn't
+be shown if it doesn't
+change. Otherwise, that
+would not be helping to
+compress the size of the
+changes.
+
+It is important to spell
+check this document. On
+the other hand, a
+misspelled word isn't
+the end of the world.
+Nothing in the rest of
+this paragraph needs to
+be changed. Things can
+be added after it.
+
+This pragraph contains
+important new additions
+to this document.
+
+

newfiles/util.c

@@ -0,0 +1,53 @@
+//
+//  util.c
+//  diff
+//
+//  Created by William McCarthy on 5/9/19.
+//  Copyright © 2019 William McCarthy. All rights reserved.
+//
+
+#include <string.h>
+#include <stdlib.h>
+#include "util.h"
+
+#define BUFLEN 256
+
+
+char* yesorno(int condition) { return condition == 0 ? "no" : "YES"; }
+
+FILE* openfile(const char* filename, const char* openflags) {
+  FILE* f;
+  if ((f = fopen(filename, openflags)) == NULL) {  printf("can't open '%s'\n", filename);  exit(1); }
+  return f;
+}
+
+void printline(void) {
+  for (int i = 0; i < 10; ++i) { printf("=========="); }
+  printf("\n");
+}
+
+
+void printleft(const char* left) {
+  char buf[BUFLEN];
+  
+  strcpy(buf, left);
+  int j = 0, len = (int)strlen(buf) - 1;
+  for (j = 0; j <= 48 - len ; ++j) { buf[len + j] = ' '; }
+  buf[len + j++] = '<';
+  buf[len + j++] = '\0';
+  printf("%s\n", buf);
+}
+
+void printright(const char* right) {
+  if (right == NULL) { return; }
+  printf("%50s %s", ">", right);
+}
+
+void printboth(const char* left_right) {
+  char buf[BUFLEN];
+  size_t len = strlen(left_right);
+  if (len > 0) { strncpy(buf, left_right, len); }
+  buf[len - 1] = '\0';
+  printf("%-50s %s", buf, left_right);
+}
+

newfiles/util.h

@@ -0,0 +1,24 @@
+//
+//  util.h
+//  diff
+//
+//  Created by William McCarthy on 5/9/19.
+//  Copyright © 2019 William McCarthy. All rights reserved.
+//
+
+#ifndef util_h
+#define util_h
+
+#include <stdio.h>
+#define BUFLEN 256
+
+char* yesorno(int condition);
+FILE* openfile(const char* filename, const char* openflags);
+
+void printleft(const char* left);
+void printright(const char* right);
+void printboth(const char* left_right);
+
+void printline(void);
+
+#endif /* util_h */