Add start of prefs reading

prefs.c

@@ -0,0 +1,111 @@
+#include "prefs.h"
+#include <ctype.h>
+
+ORCA_FORCE_NO_INLINE
+Readprefs_result prefs_read_line(FILE* file, char* buf, Usz bufsize,
+                                 Usz* out_strlen, char** out_left,
+                                 Usz* out_leftsize, char** out_right,
+                                 Usz* out_rightsize) {
+  Usz len, a0, a1, b0, b1;
+  char* s;
+  *out_strlen = 0;
+  if (bufsize < 2)
+    goto insufficient_buffer;
+#if SIZE_MAX > INT_MAX
+  if (bufsize > (Usz)INT_MAX)
+    exit(1); // he boot too big
+#endif
+  s = fgets(buf, (int)bufsize, file);
+  if (!s) {
+    if (feof(file))
+      goto eof;
+    goto ioerror;
+  }
+  len = strlen(buf);
+  if (len == bufsize - 1 && buf[len - 1] != '\n' && !feof(file))
+    goto insufficient_buffer;
+  *out_strlen = len - 1;
+  a0 = 0; // start of left
+  for (;;) {
+    if (a0 == len)
+      goto ignore;
+    char c = s[a0];
+    if (c == ';' || c == '#') // comment line, ignore
+      goto ignore;
+    if (c == '=') // '=' before any other char, bad
+      goto ignore;
+    if (!isspace(c))
+      break;
+    a0++;
+  }
+  a1 = a0; // end of left
+  for (;;) {
+    a1++;
+    if (a1 == len)
+      goto ignore;
+    char c = s[a1];
+    Usz x = a1;
+    while (isspace(c)) {
+      x++;
+      if (x == len)
+        goto ignore;
+      c = s[x];
+    }
+    if (c == '=') {
+      b0 = x;
+      break;
+    }
+    a1 = x;
+  }
+  for (;;) {
+    b0++;
+    if (b0 == len)
+      goto ignore;
+    char c = s[b0];
+    if (!isspace(c))
+      break;
+  }
+  b1 = b0; // end of right
+  for (;;) {
+    b1++;
+    if (b1 == len)
+      goto ok;
+    char c = s[b1];
+    Usz x = b1;
+    while (isspace(c)) {
+      x++;
+      if (x == len)
+        goto ok;
+      c = s[x];
+    }
+    b1 = x;
+  }
+  Readprefs_result err;
+insufficient_buffer:
+  err = Readprefs_buffer_too_small;
+  goto fail;
+eof:
+  err = Readprefs_eof;
+  goto fail;
+ioerror:
+  err = Readprefs_io_error;
+  goto fail;
+ignore:
+  s[len - 1] = '\0';
+  err = Readprefs_irrelevant;
+  goto fail;
+fail:
+  *out_left = NULL;
+  *out_leftsize = 0;
+  *out_right = NULL;
+  *out_rightsize = 0;
+  return err;
+ok:
+  s[a1] = '\0';
+  s[b1] = '\0';
+  *out_left = s + a0;
+  *out_leftsize = a1 - a0;
+  *out_right = s + b0;
+  *out_rightsize = b1 - b0;
+  return Readprefs_left_and_right;
+}

prefs.h

@@ -0,0 +1,16 @@
+#pragma once
+#include "base.h"
+#include <stdio.h> // FILE cannot be forward declared
+
+typedef enum {
+  Readprefs_left_and_right = 0,
+  Readprefs_irrelevant,
+  Readprefs_buffer_too_small,
+  Readprefs_eof,
+  Readprefs_io_error,
+} Readprefs_result;
+
+Readprefs_result prefs_read_line(FILE* file, char* buf, Usz bufsize,
+                                 Usz* out_linelen, char** out_left,
+                                 Usz* out_leftlen, char** out_right,
+                                 Usz* out_rightlen);

tool

@@ -308,7 +308,7 @@ build_target() {
       out_exe=cli
       ;;
     orca|tui)
-      add source_files osc_out.c term_util.c cboard.c tui_main.c
+      add source_files osc_out.c term_util.c cboard.c prefs.c tui_main.c
       add cc_flags -D_XOPEN_SOURCE_EXTENDED=1
       # thirdparty headers (like sokol_time.h) should get -isystem for their
       # include dir so that any warnings they generate with our warning flags