moved biggest stack buffers to malloc space, or made their size configurable

(8k of shell line edit buffer is an overkill)

# make ARCH=i386 bloatcheck
function                                             old     new   delta
read_line_input                                     3933    3967     +34
ifaddrlist                                           348     345      -3
do_loadfont                                          208     191     -17
edit_file                                            840     819     -21
.rodata                                           129112  129080     -32
uncompress                                          1305    1268     -37
loadfont_main                                        566     495     -71
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 1/6 up/down: 34/-181)          Total: -147 bytes

1 files changed, 38 insertions, 39 deletions

diff --git a/console-tools/loadfont.c b/console-tools/loadfont.c
index 88d7a0401..b046d40e3 100644
--- a/console-tools/loadfont.c
+++ b/console-tools/loadfont.c
@@ -21,43 +21,27 @@ enum {
 };
 
 struct psf_header {
-        unsigned char magic1, magic2;   /* Magic number */
-        unsigned char mode;                     /* PSF font mode */
-        unsigned char charsize;         /* Character size */
+        unsigned char magic1, magic2;   /* Magic number */
+        unsigned char mode;             /* PSF font mode */
+        unsigned char charsize;         /* Character size */
 };
 
 #define PSF_MAGIC_OK(x) ((x).magic1 == PSF_MAGIC1 && (x).magic2 == PSF_MAGIC2)
 
-static void loadnewfont(int fd);
-
-int loadfont_main(int argc, char **argv);
-int loadfont_main(int argc, char **argv)
-{
-        int fd;
-
-        if (argc != 1)
-                bb_show_usage();
-
-        fd = xopen(CURRENT_VC, O_RDWR);
-        loadnewfont(fd);
-
-        return EXIT_SUCCESS;
-}
-
 static void do_loadfont(int fd, unsigned char *inbuf, int unit, int fontsize)
 {
-        char buf[16384];
+        char *buf;
         int i;
 
-        memset(buf, 0, sizeof(buf));
-
         if (unit < 1 || unit > 32)
                 bb_error_msg_and_die("bad character size %d", unit);
 
+        buf = xzalloc(16 * 1024);
+        /*memset(buf, 0, 16 * 1024);*/
         for (i = 0; i < fontsize; i++)
                 memcpy(buf + (32 * i), inbuf + (unit * i), unit);
 
-#if defined( PIO_FONTX ) && !defined( __sparc__ )
+#if defined(PIO_FONTX) && !defined(__sparc__)
         {
                 struct consolefontdesc cfd;
 
@@ -66,12 +50,14 @@ static void do_loadfont(int fd, unsigned char *inbuf, int unit, int fontsize)
                 cfd.chardata = buf;
 
                 if (ioctl(fd, PIO_FONTX, &cfd) == 0)
-                        return;                         /* success */
-                bb_perror_msg("PIO_FONTX ioctl error (trying PIO_FONT)");
+                        goto ret;                       /* success */
+                bb_perror_msg("PIO_FONTX ioctl (will try PIO_FONT)");
         }
 #endif
         if (ioctl(fd, PIO_FONT, buf))
-                bb_perror_msg_and_die("PIO_FONT ioctl error");
+                bb_perror_msg_and_die("PIO_FONT ioctl");
+ ret:
+        free(buf);
 }
 
 static void
@@ -124,31 +110,30 @@ do_loadtable(int fd, unsigned char *inbuf, int tailsz, int fontsize)
 
 static void loadnewfont(int fd)
 {
+        enum { INBUF_SIZE = 32*1024 + 1 };
+
         int unit;
-        unsigned char inbuf[32768];                     /* primitive */
-        unsigned int inputlth, offset;
+        unsigned inputlth, offset;
+        /* Was on stack, but 32k is a bit too much: */
+        unsigned char *inbuf = xmalloc(INBUF_SIZE);
 
         /*
          * We used to look at the length of the input file
          * with stat(); now that we accept compressed files,
          * just read the entire file.
          */
-        inputlth = fread(inbuf, 1, sizeof(inbuf), stdin);
-        if (ferror(stdin))
+        inputlth = full_read(STDIN_FILENO, inbuf, INBUF_SIZE);
+        if (inputlth < 0)
                 bb_perror_msg_and_die("error reading input font");
-        /* use malloc/realloc in case of giant files;
-           maybe these do not occur: 16kB for the font,
-           and 16kB for the map leaves 32 unicode values
-           for each font position */
-        if (!feof(stdin))
-                bb_perror_msg_and_die("font too large");
+        if (inputlth >= INBUF_SIZE)
+                bb_error_msg_and_die("font too large");
 
         /* test for psf first */
         {
                 struct psf_header psfhdr;
                 int fontsize;
                 int hastable;
-                unsigned int head0, head;
+                unsigned head0, head;
 
                 if (inputlth < sizeof(struct psf_header))
                         goto no_psf;
@@ -161,7 +146,7 @@ static void loadnewfont(int fd)
                 if (psfhdr.mode > PSF_MAXMODE)
                         bb_error_msg_and_die("unsupported psf file mode");
                 fontsize = ((psfhdr.mode & PSF_MODE512) ? 512 : 256);
-#if !defined( PIO_FONTX ) || defined( __sparc__ )
+#if !defined(PIO_FONTX) || defined(__sparc__)
                 if (fontsize != 256)
                         bb_error_msg_and_die("only fontsize 256 supported");
 #endif
@@ -177,8 +162,8 @@ static void loadnewfont(int fd)
                         do_loadtable(fd, inbuf + head, inputlth - head, fontsize);
                 return;
         }
-  no_psf:
 
+ no_psf:
         /* file with three code pages? */
         if (inputlth == 9780) {
                 offset = 40;
@@ -192,3 +177,17 @@ static void loadnewfont(int fd)
         }
         do_loadfont(fd, inbuf + offset, unit, 256);
 }
+
+int loadfont_main(int argc, char **argv);
+int loadfont_main(int argc, char **argv)
+{
+        int fd;
+
+        if (argc != 1)
+                bb_show_usage();
+
+        fd = xopen(CURRENT_VC, O_RDWR);
+        loadnewfont(fd);
+
+        return EXIT_SUCCESS;
+}