baked-nobloat.c added as minor venture to reduce bloat of baked.c, reduced bloat of find_region

baked-nobloat.c

@@ -0,0 +1,245 @@
+/* baked-nobloat.c - cake makes you fat. This version just removes features I don't find entirely necessary ($+, require space, shake support, ctype, and options).
+ * Copyright 2023 Emil Williams
+ * Licensed under the GNU Public License version 3 only, see LICENSE.
+ * @EXEC cc $@ -o $* -std=gnu89 -O2 -Wall -Wextra -Wpedantic -pipe $CFLAGS STOP@
+ */
+
+#include <errno.h>
+#include <fcntl.h>
+#include <locale.h>
+#include <stddef.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/mman.h>
+#include <sys/stat.h>
+#include <unistd.h>
+
+#define START "@EXEC"
+#define  STOP "STOP@"
+#define  HELP                                                                          \
+    "target-file [arguments ...]\n"                                                    \
+    "Use the format `@EXEC cmd ...' within the target-file, this will execute the\n"   \
+    "rest of line, or if found within the file, until the STOP@ marker.\n"
+
+#define DESC                                                \
+  "Expansions\n"                                            \
+  "\t$@  returns target-file                (abc.x.txt)\n"  \
+  "\t$*  returns target-file without suffix (^-> abc.x)\n"
+
+static char * g_filename, * g_short;
+
+static char *
+map(const char * fn, size_t * len)
+{
+  struct stat s;
+  int fd;
+  char * addr = NULL;
+  fd = open(fn, O_RDONLY);
+  if (fd != -1)
+  {
+    if (!fstat(fd,&s)
+        &&   s.st_mode & S_IFREG
+        &&   s.st_size)
+    {
+      *len = s.st_size;
+      addr = mmap(NULL, s.st_size, PROT_READ, MAP_SHARED, fd, 0);
+      if (addr == MAP_FAILED)
+      { addr = NULL; }
+    }
+    close(fd);
+  }
+  return addr;
+}
+
+static const char *
+find(const char * x, const char * buf, const size_t max, const size_t min)
+{
+  const char * start = buf;
+  for (; *buf; ++buf)
+  {
+    if (max - (buf - start) > min && !strncmp(buf, x, min))
+    { return buf; }
+  }
+  return NULL;
+}
+
+static char *
+find_region(char * addr, size_t len)
+{
+  char * buf = NULL;
+  const char * start, * stop;
+  if ((start = find(START, addr, len, strlen(START))))
+  {
+    start += strlen(START);
+    stop = find(STOP, start, len - (start - addr), strlen(STOP));
+    if (!stop)
+    {
+      stop = start;
+      while (*stop && *stop != '\n')
+      {
+        if (stop[0] == '\\' && stop[1] == '\n')
+        { stop += 2; }
+        ++stop;
+      }
+    }
+    if (stop)
+    { buf = strndup(start, (stop - addr) - (start - addr)); }
+  }
+  return buf;
+}
+
+static void
+swap(char * a, char * b)
+{
+  *a ^= *b;
+  *b ^= *a;
+  *a ^= *b;
+}
+
+static int
+root(char * root)
+{
+  int ret;
+  char x[1] = "\0";
+  size_t len = strlen(root);
+  while (len && root[len] != '/')
+  { --len; }
+  if (!len)
+  { return 0; }
+  swap(root + len, x);
+  ret = chdir(root);
+  swap(root + len, x);
+  return ret;
+}
+
+static char *
+insert(const char * new, char * str, size_t offset, size_t shift)
+{
+  size_t len, max;
+  if (!new) { return str; }
+  if (!str) { return NULL; }
+  len = strlen(new);
+  max = (strlen(str) + 1 - offset - shift);
+  memmove(str + offset + len, str + offset + shift, max);
+  memcpy(str + offset, new, len);
+  return str;
+}
+
+static char *
+shorten(char * fn)
+{
+  size_t i, last = 0, len;
+  char * sh;
+  len = strlen(fn);
+  sh = malloc(len + 1);
+  if (!sh) { return NULL; }
+  for (i = 0; i < len; ++i)
+  {
+    if (fn[i] == '.')
+    { last = i; }
+  }
+  last = last ? last : i;
+  strncpy(sh, fn, last);
+  sh[last] = '\0';
+  return sh;
+}
+
+static size_t
+expand_size(char * buf)
+{
+  size_t i, len, max;
+  len = max = strlen(buf) + 1;
+  for (i = 0; i < len; ++i)
+  {
+    if (buf[i] == '\\')
+    { i += 2; continue; }
+    else if (buf[i] == '$')
+    {
+      switch (buf[++i])
+      {
+      case '@':
+        max += strlen(g_filename);
+        break;
+      case '*':
+        if (!g_short)
+        { g_short = shorten(g_filename); }
+        max += g_short ? strlen(g_short) : 0;
+        break;
+      }
+    }
+  }
+  return max;
+}
+
+static char *
+expand(char * buf)
+{
+  size_t i;
+  char * ptr = NULL;
+  buf = realloc(buf, expand_size(buf));
+  if (!buf) { return NULL; }
+  for (i = 0; buf[i]; ++i)
+  {
+    if (buf[i] == '\\')
+    { i += 2; continue; }
+    else if (buf[i] == '$')
+    {
+      switch (buf[++i])
+      {
+      case '@':
+        ptr = g_filename;
+        break;
+      case '*':
+        ptr = g_short;
+        break;
+      default: continue;
+      }
+      buf = insert(ptr, buf, i - 1, 2);
+    }
+  }
+  free(g_short);
+  return buf;
+}
+
+static int
+run(const char * buf)
+{
+  fputs("Output:\n", stderr);
+  root(g_filename);
+  return system(buf);
+}
+
+int
+main(int argc, char ** argv)
+{
+  int ret = 0;
+  char * buf = NULL, * addr;
+  size_t len;
+  setlocale(LC_ALL, "C");
+  if (argc < 2)
+  { goto help; }
+  g_filename = argv[1];
+  if ((addr = map(g_filename,  &len)))
+  {
+    buf = find_region(addr, len);
+    munmap(addr, len);
+  }
+  if (!buf)
+  {
+    if (errno)
+    { perror(argv[0]); }
+    else
+    { fprintf(stderr, "%s: File unrecognized.\n", argv[0]); }
+    return 1;
+  }
+  buf = expand(buf);
+  fprintf(stderr, "Exec: %s\n", buf ? buf + 1 : buf);
+  if ((ret = ret ? 0 : run(buf)))
+  { fprintf(stderr, "Result: %d\n", ret); }
+  free(buf);
+  return ret;
+help:
+  fprintf(stderr, "%s: %s", argv[0], HELP DESC);
+  return 1;
+}

baked.c

@@ -47,6 +47,29 @@
 
 static char * g_filename, * g_short, * g_all;
 
+static char *
+map(const char * fn, size_t * len)
+{
+  struct stat s;
+  int fd;
+  char * addr = NULL;
+  fd = open(fn, O_RDONLY);
+  if (fd != -1)
+  {
+    if (!fstat(fd,&s)
+        &&   s.st_mode & S_IFREG
+        &&   s.st_size)
+    {
+      *len = s.st_size;
+      addr = mmap(NULL, s.st_size, PROT_READ, MAP_SHARED, fd, 0);
+      if (addr == MAP_FAILED)
+      { addr = NULL; }
+    }
+    close(fd);
+  }
+  return addr;
+}
+
 static const char *
 find(const char * x, const char * buf, const size_t max, const size_t min)
 {
@@ -60,76 +83,57 @@ find(const char * x, const char * buf, const size_t max, const size_t min)
 }
 
 static char *
-find_region(const char * fn)
+find_region(char * addr, size_t len)
 {
-  struct stat s;
-  int fd;
   char * buf = NULL;
-
-  fd = open(fn, O_RDONLY);
-
-  if (fd != -1)
-  {
-    if (!fstat(fd,&s)
-        &&   s.st_mode & S_IFREG
-        &&   s.st_size)
-    {
-      const char * start, * stop;
-      char * addr;
-      addr = mmap(NULL, s.st_size, PROT_READ, MAP_SHARED, fd, 0);
-      if (addr != MAP_FAILED)
-      {
-        start = find(START, addr, s.st_size, strlen(START));
+  const char * start, * stop;
+  start = find(START, addr, len, strlen(START));
 #ifdef OTHER_START
-        if (!start)
-        {
-          start = find(OTHER_START, addr, s.st_size, strlen(OTHER_START));
-          start = (const char *) /* DON'T QUESTION IT */
-                 ((ptrdiff_t) (start - strlen(START) + strlen(OTHER_START)) * (start != 0));
-        }
+  if (!start)
+  {
+    start = find(OTHER_START, addr, len, strlen(OTHER_START));
+    start = (const char *) /* DON'T QUESTION IT */
+      ((ptrdiff_t) (start - strlen(START) + strlen(OTHER_START)) * (start != 0));
+  }
 #endif /* OTHER_START */
-        if (start)
-        {
-          start += strlen(START);
+  if (start)
+  {
+    start += strlen(START);
 #ifdef REQUIRE_SPACE
-          if (!isspace(*start))
-          {
-            fprintf(stderr, "ERROR: Found start without suffix spacing.\n");
-            return NULL;
-          }
+    if (!isspace(*start))
+    {
+      fprintf(stderr, "ERROR: Found start without suffix spacing.\n");
+      return NULL;
+    }
 #endif
-          stop = find(STOP, start, s.st_size - (start - addr), strlen(STOP));
-          if (!stop)
-          {
-            stop = start;
-            while (*stop && *stop != '\n')
-            {
-              if (stop[0] == '\\' && stop[1] == '\n')
-              { stop += 2; }
-              ++stop;
-            }
-          }
+    stop = find(STOP, start, len - (start - addr), strlen(STOP));
+    if (!stop)
+    {
+      stop = start;
+      while (*stop && *stop != '\n')
+      {
+        if (stop[0] == '\\' && stop[1] == '\n')
+        { stop += 2; }
+        ++stop;
+      }
+    }
 #ifdef REQUIRE_SPACE
-          else
-          {
-            if (!isspace(*(stop - 1)))
-            {
-              fprintf(stderr, "ERROR: Found stop without prefixing spacing.\n");
-              return NULL;
-            }
-          }
-#endif
-          if (stop)
-          { buf = strndup(start, (stop - addr) - (start - addr)); }
-        }
-        munmap(addr, s.st_size);
+    else
+    {
+      if (!isspace(*(stop - 1)))
+      {
+        fprintf(stderr, "ERROR: Found stop without prefixing spacing.\n");
+        return NULL;
       }
     }
-    close(fd);
+#endif
+    if (stop)
+    { buf = strndup(start, (stop - addr) - (start - addr)); }
   }
   return buf;
 }
 
+
 static void
 swap(char * a, char * b)
 {
@@ -299,7 +303,8 @@ int
 main(int argc, char ** argv)
 {
   int ret = 0;
-  char * buf;
+  char * buf = NULL, * addr;
+  size_t len;
   assert(setlocale(LC_ALL, "C"));
 
   if (argc < 2
@@ -318,7 +323,12 @@ main(int argc, char ** argv)
     { goto help; }
   }
 
-  buf = find_region(g_filename);
+  if ((addr = map(g_filename,  &len)))
+  {
+    buf = find_region(addr, len);
+    munmap(addr, len);
+  }
+
   if (!buf)
   {
     if (errno)