Suggested changes around binary files, restructured map

bake.c

@@ -36,7 +36,6 @@
     "@COMPILECMD instead of @EXEC.  Whitespace is required after and before both\n"    \
     "operators always.\n"
 
-
 #define DESC                                                \
   "Options [Must always be first]\n"                        \
   "\t-h --help, -n --dry-run\n"                             \
@@ -45,137 +44,30 @@
   "\t$*  returns target-file without suffix (^-> abc.x)\n"  \
   "\t$+  returns arguments\n"
 
-#define local_assert(expr, ret) do { assert(expr); if (!expr) { return ret; }} while (0)
-
-static char * g_filename, * g_short, * g_all;
-
-static char *
-map(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);
-    }
-    close(fd);
-  }
-  return addr;
-}
+static char * g_filename;
 
-static char *
-find(char * x, char * buf, size_t max, size_t min)
-{
-  char * start = buf;
-  for (; *buf; ++buf)
-  {
-    if (max - (buf - start) > min
-    && !strncmp(buf, x, min))
-    { return buf; }
-  }
-  return NULL;
-}
-
-static char *
-find_region(char * fn)
-{
-  size_t len = 0;
-  char * buf = NULL, * addr;
-  char * start, * stop;
-  addr = map(fn, &len);
-  if ((ptrdiff_t) addr > 0)
-  {
-    start = find(START, addr, len, strlen(START));
-#ifdef OTHER_START
-    if (!start)
-    {
-      start = find(OTHER_START, addr, len, strlen(OTHER_START));
-      start = (char *) /* DON'T QUESTION IT */
-        ((ptrdiff_t) (start - strlen(START) + strlen(OTHER_START)) * (start != 0));
-    }
-#endif /* OTHER_START */
-    if (start)
-    {
-      start += strlen(START);
-#ifdef REQUIRE_SPACE
-      if (!isspace(*start))
-      {
-        fprintf(stderr, "ERROR: Found start without suffix spacing.\n");
-        goto stop;
-      }
-#endif
-      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");
-          goto stop;
-        }
-      }
-#endif
-      if (stop)
-      { buf = strndup(start, (stop - addr) - (start - addr)); }
-    }
-  stop:
-    munmap(addr, len);
-  }
-  return buf;
-}
+/*** Utility functions ***/
 
 static void
-swap(char * a, char * b)
-{
+swap(char * a, char * b) {
   *a ^= *b;
   *b ^= *a;
   *a ^= *b;
 }
 
-static int
-root(char ** rootp)
-{
-  char x[1] = "\0";
-  char * root = *rootp;
-  size_t len = strlen(root);
-  int ret;
-  while (len
-      && root[len] != '/')
-  { --len; }
-  if (!len)
-  { return 0; }
-  swap(root + len, x);
-  ret = chdir(root);
-  swap(root + len, x);
-  *rootp += len + 1;
-  return ret;
+static char *
+find(char * x, char * buf, char * end) {
+  size_t len = strlen(x);
+  for (; (buf < end) && len < (size_t)(end - buf); ++buf) {
+    if (!strncmp(buf, x, len))
+    { return buf; }
+  }
+  return NULL;
 }
 
 static char *
-insert(char * new, char * str, size_t offset, size_t shift)
-{
+insert(char * new, char * str, size_t offset, size_t shift) {
   size_t len, max;
-  local_assert(new, str);
-  local_assert(str, NULL);
   len = strlen(new);
   max = (strlen(str) + 1 - offset - shift);
   memmove(str + offset + len, str + offset + shift, max);
@@ -183,19 +75,19 @@ insert(char * new, char * str, size_t offset, size_t shift)
   return str;
 }
 
+/*** g_short, g_all Functions ***/
+
+static char * g_short, * g_all;
+
 static char *
-shorten(char * fn)
-{
+shorten(char * fn) {
   size_t i, last = 0, len;
   char * sh;
-  local_assert(fn, NULL);
   len = strlen(fn);
   sh = malloc(len + 1);
-  local_assert(sh, NULL);
-  for (i = 0; i < len; ++i)
-  {
-    if (fn[i] == '.')
-    { last = i; }
+  if (!sh) { return NULL; }
+  for (i = 0; i < len; ++i) {
+    if (fn[i] == '.') { last = i; }
   }
   last = last ? last : i;
   strncpy(sh, fn, last);
@@ -204,53 +96,128 @@ shorten(char * fn)
 }
 
 static char *
-all_args(size_t argc, char ** argv)
-{
+all_args(size_t argc, char ** argv) {
   char * all = NULL;
-  if (argc > 2)
-  {
+  if (argc > 2) {
     size_t i, len = argc;
-    for (i = 2; i < argc; ++i)
-    { len += strlen(argv[i]); }
+    for (i = 2; i < argc; ++i) { len += strlen(argv[i]); }
     all = malloc(len + 1);
-    local_assert(all, NULL);
+    if (!all) { return NULL; }
     all[len] = '\0';
     len = 0;
-    for (i = 2; i < argc; ++i)
-    {
+    for (i = 2; i < argc; ++i) {
       strcpy(all + len, argv[i]);
       len += strlen(argv[i]) + 1;
-      if (i + 1 < argc)
-      { all[len - 1] = ' '; }
+      if (i + 1 < argc) { all[len - 1] = ' '; }
     }
   }
   return all;
 }
 
+/*** Map ***/
+
+typedef struct {
+  char * str;
+  size_t len;
+} map_t;
+
+static map_t
+map(char * fn) {
+  struct stat s;
+  int fd;
+  map_t fs = {0};
+  fd = open(fn, O_RDONLY);
+  if (fd != -1) {
+    if (!fstat(fd,&s)
+    &&   s.st_mode & S_IFREG
+    &&   s.st_size) {
+      fs.len = s.st_size;
+      fs.str = (char *) mmap(NULL, s.st_size, PROT_READ, MAP_SHARED, fd, 0);
+    }
+    close(fd);
+  }
+  return fs;
+}
+
+/*** Important Functions ***/
+
+static char *
+find_region(map_t m) {
+  char * buf = NULL;
+  char * start, * stop;
+  start = find(START, m.str, m.str + m.len);
+#ifdef OTHER_START
+  if (!start) {
+    start = find(OTHER_START, m.str, m.str + m.len);
+    start = (char *) /* DON'T QUESTION IT */
+      ((ptrdiff_t) (start - strlen(START) + strlen(OTHER_START)) * (start != 0));
+  }
+#endif /* OTHER_START */
+  if (start) {
+    start += strlen(START);
+#ifdef REQUIRE_SPACE
+    if (!isspace(*start)) {
+      fprintf(stderr, "ERROR: Found start without suffix spacing.\n");
+      return buf;
+    }
+#endif
+    stop = find(STOP, start, start + m.len - (start - m.str));
+    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 buf;
+      }
+    }
+#endif
+    if (stop) { buf = strndup(start, (stop - m.str) - (start - m.str)); }
+  }
+  return buf;
+}
+
+static int
+root(char ** rootp) {
+  char x[1] = "\0";
+  char * root = *rootp;
+  size_t len = strlen(root);
+  int ret;
+  while (len
+     && root[len] != '/')
+  { --len; }
+  if (!len) { return 0; }
+  swap(root + len, x);
+  ret = chdir(root);
+  swap(root + len, x);
+  *rootp += len + 1;
+  return ret;
+}
+
 static size_t
-expand_size(char * buf, int argc, char ** argv)
-{
+expand_size(char * buf, int argc, char ** argv) {
   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] == '$')
-    {
-      switch (buf[++i])
-      {
+  for (i = 0; i < len; ++i) {
+    if (buf[i] == '\\') { i += 2; continue; }
+    else if (buf[i] == '$') {
+      switch (buf[++i]) {
       case '@':
         max += strlen(g_filename);
         break;
       case '*':
-        if (!g_short)
-        { g_short = shorten(g_filename); }
+        if (!g_short) { g_short = shorten(g_filename); }
         max += g_short ? strlen(g_short) : 0;
         break;
       case '+':
-        if (!g_all)
-        { g_all = all_args((size_t) argc, argv); }
+        if (!g_all) { g_all = all_args((size_t) argc, argv); }
         max += g_all ? strlen(g_all) : 0;
         break;
       }
@@ -260,18 +227,13 @@ expand_size(char * buf, int argc, char ** argv)
 }
 
 static char *
-expand(char * buf)
-{
+expand(char * buf) {
   size_t i;
   char * ptr = NULL;
-  for (i = 0; buf[i]; ++i)
-  {
-    if (buf[i] == '\\')
-    { i += 2; continue; }
-    else if (buf[i] == '$')
-    {
-      switch (buf[++i])
-      {
+  for (i = 0; buf[i]; ++i) {
+    if (buf[i] == '\\') { i += 2; continue; }
+    else if (buf[i] == '$') {
+      switch (buf[++i]) {
       case '@':
         ptr = g_filename;
         break;
@@ -291,30 +253,25 @@ expand(char * buf)
 }
 
 static size_t
-strip(char * buf)
-{
+strip(char * buf) {
   size_t i = strlen(buf);
-  if (!i)
-  { return 0; }
-  while (isspace(buf[i - 1]))
-  { --i; }
+  if (!i) { return 0; }
+  while (isspace(buf[i - 1])) { --i; }
   buf[i] = '\0';
   for (i = 0; isspace(buf[i]); ++i);
   return i - (buf[i - 1] == '\n');
 }
 
 static int
-run(char * buf)
-{
+run(char * buf) {
   fputs("Output:\n", stderr);
   return system(buf);
 }
 
 int
-main(int argc, char ** argv)
-{
+main(int argc, char ** argv) {
   int ret = 0;
-  char * buf;
+  char * buf = NULL;
 
   setlocale(LC_ALL, "C");
 
@@ -326,28 +283,27 @@ main(int argc, char ** argv)
   g_filename = argv[1];
 
   if (!strcmp(argv[1], "-n")
-  ||  !strcmp(argv[1], "--dry-run"))
-  {
-    if (argc > 2)
-    { ret = 1; g_filename = argv[2]; }
-    else
-    { goto help; }
+  ||  !strcmp(argv[1], "--dry-run")) {
+    if (argc > 2) { ret = 1; g_filename = argv[2]; }
+    else { goto help; }
   }
 
-  buf = find_region(g_filename);
+  { map_t m = map(argv[1]);
+    if (m.str) {
+      buf = find_region(m);
+      munmap(m.str, m.len);
+    }
+  }
 
-  if (!buf)
-  {
-    if (errno)
-    { perror(argv[0]); }
-    else
-    { fprintf(stderr, "%s: File unrecognized.\n", argv[0]); }
+  if (!buf) {
+    if (errno) { perror(argv[0]); }
+    else { fprintf(stderr, "%s: File unrecognized.\n", argv[0]); }
     return 1;
   }
 
   root(&g_filename);
   buf = realloc(buf, expand_size(buf, argc, argv));
-  local_assert(buf, 1);
+  if (!buf) { free(g_short); free(g_all); return 1; }
   buf = expand(buf);
   fprintf(stderr, "Exec: %s\n", buf + strip(buf));
   if ((ret = ret ? 0 : run(buf)))