Home-grown APIs, reduced binary size (<40KB)

diff --git a/nnn.c b/nnn.c
index 6e6c1ca3cfcec8f7f020e97606b99da037844c5d..04568247ec8d59f4219a3d1cb89338520346be6a 100644 (file)
--- a/nnn.c
+++ b/nnn.c
@@ -178,6 +178,7 @@ static size_t fs_free;
 static uint open_max;
 static bm bookmark[MAX_BM];
 static const double div_2_pow_10 = 1.0 / 1024.0;
+static uint _WSHIFT;
 
 /* Utilities to open files, run actions */
 static char *utils[] = {
@@ -239,15 +240,96 @@ max_openfds()
        return 32;
 }
 
-/* Just a safe strncpy(3) */
-static void
+/*
+ * Custom xstrlen()
+ */
+static size_t
+xstrlen(const char *s)
+{
+       static size_t len;
+
+       if (!s)
+               return 0;
+
+       len = 0;
+       while (*s) {
+               ++len, ++s;
+       }
+
+       return len;
+}
+
+/*
+ * Just a safe strncpy(3)
+ * Always null ('\0') terminates if both src and dest are valid pointers.
+ * Returns the number of bytes copied including terminating null byte.
+ */
+static size_t
 xstrlcpy(char *dest, const char *src, size_t n)
 {
+       static size_t len, blocks;
+
+       if (!src || !dest)
+               return 0;
+
+       len = xstrlen(src) + 1;
+       if (n > len)
+               n = len;
+       else if (len > n)
+               /* Save total number of bytes to copy in len */
+               len = n;
+
+       blocks = n >> _WSHIFT;
+       n -= (blocks << _WSHIFT);
+
+       if (blocks) {
+               static ulong *s, *d;
+
+               s = (ulong *)src;
+               d = (ulong *)dest;
+
+               while (blocks) {
+                       *d = *s;
+                       ++d, ++s;
+                       --blocks;
+               }
+
+               if (!n) {
+                       dest = (char *)d;
+                       *--dest = '\0';
+                       return len;
+               }
+
+               src = (char *)s;
+               dest = (char *)d;
+       }
+
        while (--n && (*dest = *src))
                ++dest, ++src;
 
        if (!n)
                *dest = '\0';
+
+       return len;
+}
+
+/*
+ * Custom strcmp(), just what we need.
+ * Returns 0 if same, else -1
+ */
+static int
+xstrcmp(const char *s1, const char *s2)
+{
+       if (!s1 || !s2)
+               return -1;
+
+       while (*s1 && *s1 == *s2)
+               ++s1, ++s2;
+
+       if (*s1 != *s2)
+               return -1;
+
+       return 0;
 }
 
 /*
@@ -518,7 +600,7 @@ strstrip(char *s)
        if (!s || !*s)
                return s;
 
-       size_t len = strlen(s) - 1;
+       size_t len = xstrlen(s) - 1;
 
        while (len != 0 && (isspace(s[len]) || s[len] == '/'))
                --len;
@@ -868,7 +950,7 @@ mkpath(char *dir, char *name, char *out, size_t n)
                xstrlcpy(out, name, n);
        else {
                /* Handle root case */
-               if (strcmp(dir, "/") == 0)
+               if (dir[0] == '/' && dir[1] == '\0')
                        snprintf(out, n, "/%s", name);
                else
                        snprintf(out, n, "%s/%s", dir, name);
@@ -1612,7 +1694,7 @@ dentfind(struct entry *dents, int n, char *path)
        DPRINTF_S(p);
 
        for (i = 0; i < n; ++i)
-               if (strcmp(p, dents[i].name) == 0)
+               if (xstrcmp(p, dents[i].name) == 0)
                        return i;
 
        return 0;
@@ -1657,7 +1739,7 @@ redraw(char *path)
        erase();
 
        /* Strip trailing slashes */
-       for (i = strlen(path) - 1; i > 0; --i)
+       for (i = xstrlen(path) - 1; i > 0; --i)
                if (path[i] == '/')
                        path[i] = '\0';
                else
@@ -1675,7 +1757,8 @@ redraw(char *path)
        ncols = COLS;
        if (ncols > PATH_MAX)
                ncols = PATH_MAX;
-       g_buf[ncols - strlen(CWD) - 1] = '\0';
+       /* - xstrlen(CWD) - 1 = 6 */
+       g_buf[ncols - 6] = '\0';
        printw(CWD "%s\n\n", g_buf);
 
        if (cfg.showcolor) {
@@ -2069,7 +2152,7 @@ nochange:
                        if (truecd == 0) {
                                /* Probable change in dir */
                                /* No-op if it's the same directory */
-                               if (strcmp(path, newpath) == 0)
+                               if (xstrcmp(path, newpath) == 0)
                                        break;
 
                                oldpath[0] = '\0';
@@ -2102,7 +2185,7 @@ nochange:
                                goto nochange;
                        }
 
-                       if (strcmp(path, tmp) == 0)
+                       if (xstrcmp(path, tmp) == 0)
                                break;
 
                        /* Save last working directory */
@@ -2122,7 +2205,7 @@ nochange:
                                goto nochange;
                        }
 
-                       if (strcmp(path, ipath) == 0)
+                       if (xstrcmp(path, ipath) == 0)
                                break;
 
                        /* Save last working directory */
@@ -2166,7 +2249,7 @@ nochange:
                        clearprompt();
 
                        for (r = 0; bookmark[r].key && r < MAX_BM; ++r) {
-                               if (strcmp(bookmark[r].key, tmp) == 0) {
+                               if (xstrcmp(bookmark[r].key, tmp) == 0) {
                                        if (bookmark[r].loc[0] == '~') {
                                                /* Expand ~ to HOME */
                                                char *home = getenv("HOME");
@@ -2191,7 +2274,7 @@ nochange:
                                                goto nochange;
                                        }
 
-                                       if (strcmp(path, newpath) == 0)
+                                       if (xstrcmp(path, newpath) == 0)
                                                break;
 
                                        oldpath[0] = '\0';
@@ -2325,7 +2408,7 @@ nochange:
                        goto begin;
                case SEL_COPY:
                        if (copier && ndents) {
-                               if (strcmp(path, "/") == 0)
+                               if (path[0] == '/' && path[1] == '\0')
                                        snprintf(newpath, PATH_MAX, "/%s",
                                                 dents[cur].name);
                                else
@@ -2435,6 +2518,14 @@ main(int argc, char *argv[])
                }
        }
 
+       /* Set the word shift */
+       _WSHIFT = sizeof(ulong);
+       if (_WSHIFT == 8)
+               _WSHIFT = 3;
+       else
+               _WSHIFT = 2;
+
+       /* Increase current open file descriptor limit */
        open_max = max_openfds();
 
        if (getuid() == 0)