httpd: code shrink of dir indexer example
diff --git a/networking/httpd_indexcgi.c b/networking/httpd_indexcgi.c
index def8632..fd64af3 100644
--- a/networking/httpd_indexcgi.c
+++ b/networking/httpd_indexcgi.c
@@ -5,7 +5,7 @@
*/
/*
- * This program is a CGI application. It creates directory index page.
+ * This program is a CGI application. It outputs directory index page.
* Put it into cgi-bin/index.cgi and chmod 0755.
*/
@@ -23,14 +23,16 @@
-march=i386 -mpreferred-stack-boundary=2 \
-Wl,-Map -Wl,link.map -Wl,--warn-common -Wl,--sort-common -Wl,--gc-sections \
httpd_indexcgi.c -o index.cgi
-
-Size (approximate):
- text data bss dec hex filename
-22642 160 3052 25854 64fe index.cgi
*/
-/* TODO: get rid of printf's: printf code is more than 50%
- * of the entire executable when built against static uclibc */
+/* We don't use printf, as it pulls in >12 kb of code from uclibc (i386). */
+/* Currently malloc machinery is the biggest part of libc we pull in. */
+/* We have only one realloc and one strdup, any idea how to do without? */
+/* Size (i386, approximate):
+ * text data bss dec hex filename
+ * 13036 44 3052 16132 3f04 index.cgi
+ * 2576 4 2048 4628 1214 index.cgi.o
+ */
#include <sys/types.h>
#include <sys/stat.h>
@@ -47,149 +49,44 @@
* formatting code uses <TAG class=CLASS> to apply style
* to elements. Edit stylesheet to your liking and recompile. */
-static const char str_header[] =
-"" /* Additional headers (currently none) */
-"\r\n" /* Mandatory empty line after headers */
-"<html><head><title>Index of %s</title>" "\n"
-"<style>" "\n"
-"table {" "\n"
-" width: 100%%;" "\n"
-" background-color: #fff5ee;" "\n"
-" border-width: 1px;" /* 1px 1px 1px 1px; */ "\n"
-" border-spacing: 2px;" "\n"
-" border-style: solid;" /* solid solid solid solid; */ "\n"
-" border-color: black;" /* black black black black; */ "\n"
-" border-collapse: collapse;" "\n"
-"}" "\n"
-"th {" "\n"
-" border-width: 1px;" /* 1px 1px 1px 1px; */ "\n"
-" padding: 1px;" /* 1px 1px 1px 1px; */ "\n"
-" border-style: solid;" /* solid solid solid solid; */ "\n"
-" border-color: black;" /* black black black black; */ "\n"
-"}" "\n"
-"td {" "\n"
- /* top right bottom left */
-" border-width: 0px 1px 0px 1px;" "\n"
-" padding: 1px;" /* 1px 1px 1px 1px; */ "\n"
-" border-style: solid;" /* solid solid solid solid; */ "\n"
-" border-color: black;" /* black black black black; */ "\n"
-"}" "\n"
-"tr.hdr { background-color:#eee5de; }" "\n"
-"tr.o { background-color:#ffffff; }" "\n"
-/* tr.e { ... } - for even rows (currently none) */
-"tr.foot { background-color:#eee5de; }" "\n"
-"th.cnt { text-align:left; }" "\n"
-"th.sz { text-align:right; }" "\n"
-"th.dt { text-align:right; }" "\n"
-"td.sz { text-align:right; }" "\n"
-"td.dt { text-align:right; }" "\n"
-"col.nm { width: 98%%; }" "\n"
-"col.sz { width: 1%%; }" "\n"
-"col.dt { width: 1%%; }" "\n"
-"</style>" "\n"
-"</head>" "\n"
-"<body>" "\n"
-"<h1>Index of %s</h1>" "\n"
-"" "\n"
-"<table>" "\n"
-"<col class=nm><col class=sz><col class=dt>" "\n"
-"<tr class=hdr><th class=cnt>Name<th class=sz>Size<th class=dt>Last modified" "\n"
-;
-
-static const char str_footer[] =
-"<tr class=foot><th class=cnt>Files: %u, directories: %u<th class=sz>%llu<th class=dt> " "\n"
-/* "</table></body></html>" - why bother? */
-;
-
-static int bad_url_char(unsigned c)
-{
- return (c - '0') > 9 /* not a digit */
- && ((c|0x20) - 'a') > 26 /* not A-Z or a-z */
- && !strchr("._-+@", c);
-}
-
-static char *url_encode(const char *name)
-{
- int i;
- int size = 0;
- int len = strlen(name);
- char *p, *result;
-
- i = 0;
- while (name[i]) {
- if (bad_url_char((unsigned)name[i]))
- size++;
- i++;
- }
-
- /* No %xx needed! */
- if (!size)
- return (char*)name;
-
- /* Each %xx requires 2 additional chars */
- size = size * 2 + len + 1;
- p = result = malloc(size);
-
- i = 0;
- while (name[i]) {
- *p = name[i];
- if (bad_url_char((unsigned)name[i])) {
- *p++ = '%';
- *p++ = "0123456789ABCDEF"[(uint8_t)(name[i]) >> 4];
- *p = "0123456789ABCDEF"[(uint8_t)(name[i]) & 0xf];
- }
- p++;
- i++;
- }
- *p = 0;
- return result;
-}
-
-static char *html_encode(const char *name)
-{
- int i;
- int size = 0;
- int len = strlen(name);
- char *p, *result;
-
- i = 0;
- while (name[i]) {
- if (name[i] == '<'
- || name[i] == '>'
- || name[i] == '&'
- ) {
- size++;
- }
- i++;
- }
-
- /* No < etc needed! */
- if (!size)
- return (char*)name;
-
- /* & requires 4 additional chars */
- size = size * 4 + len + 1;
- p = result = malloc(size);
-
- i = 0;
- while (name[i]) {
- char c;
- *p = c = name[i++];
- if (c == '<')
- strcpy(p, "<");
- else if (c == '>')
- strcpy(p, ">");
- else if (c == '&')
- strcpy(++p, "amp;");
- else {
- p++;
- continue;
- }
- p += 4;
- }
- *p = 0;
- return result;
-}
+#define STYLE_STR \
+"<style>" "\n"\
+"table {" "\n"\
+ "width:100%;" "\n"\
+ "background-color:#fff5ee;" "\n"\
+ "border-width:1px;" /* 1px 1px 1px 1px; */ "\n"\
+ "border-spacing:2px;" "\n"\
+ "border-style:solid;" /* solid solid solid solid; */ "\n"\
+ "border-color:black;" /* black black black black; */ "\n"\
+ "border-collapse:collapse;" "\n"\
+"}" "\n"\
+"th {" "\n"\
+ "border-width:1px;" /* 1px 1px 1px 1px; */ "\n"\
+ "padding:1px;" /* 1px 1px 1px 1px; */ "\n"\
+ "border-style:solid;" /* solid solid solid solid; */ "\n"\
+ "border-color:black;" /* black black black black; */ "\n"\
+"}" "\n"\
+"td {" "\n"\
+ /* top right bottom left */ \
+ "border-width:0px 1px 0px 1px;" "\n"\
+ "padding:1px;" /* 1px 1px 1px 1px; */ "\n"\
+ "border-style:solid;" /* solid solid solid solid; */ "\n"\
+ "border-color:black;" /* black black black black; */ "\n"\
+ "white-space:nowrap;" "\n"\
+"}" "\n"\
+"tr.hdr { background-color:#eee5de; }" "\n"\
+"tr.o { background-color:#ffffff; }" "\n"\
+/* tr.e { ... } - for even rows (currently none) */ \
+"tr.foot { background-color:#eee5de; }" "\n"\
+"th.cnt { text-align:left; }" "\n"\
+"th.sz { text-align:right; }" "\n"\
+"th.dt { text-align:right; }" "\n"\
+"td.sz { text-align:right; }" "\n"\
+"td.dt { text-align:right; }" "\n"\
+"col.nm { width:98%; }" "\n"\
+"col.sz { width:1%; }" "\n"\
+"col.dt { width:1%; }" "\n"\
+"</style>" "\n"\
typedef struct dir_list_t {
char *dl_name;
@@ -200,8 +97,8 @@
static int compare_dl(dir_list_t *a, dir_list_t *b)
{
+ /* ".." is 'less than' any other dir entry */
if (strcmp(a->dl_name, "..") == 0) {
- /* ".." is 'less than' any other dir entry */
return -1;
}
if (strcmp(b->dl_name, "..") == 0) {
@@ -209,12 +106,110 @@
}
if (S_ISDIR(a->dl_mode) != S_ISDIR(b->dl_mode)) {
/* 1 if b is a dir (and thus a is 'after' b, a > b),
- * else -1 (a < b)*/
+ * else -1 (a < b) */
return (S_ISDIR(b->dl_mode) != 0) ? 1 : -1;
}
return strcmp(a->dl_name, b->dl_name);
}
+static char buffer[2*1024 > sizeof(STYLE_STR) ? 2*1024 : sizeof(STYLE_STR)];
+static char *dst = buffer;
+enum {
+ BUFFER_SIZE = sizeof(buffer),
+ HEADROOM = 64,
+};
+
+/* After this call, you have at least size + HEADROOM bytes available
+ * ahead of dst */
+static void guarantee(int size)
+{
+ if (buffer + (BUFFER_SIZE-HEADROOM) - dst >= size)
+ return;
+ write(1, buffer, dst - buffer);
+ dst = buffer;
+}
+
+/* NB: formatters do not store terminating NUL! */
+
+/* HEADROOM bytes are available after dst after this call */
+static void fmt_str(/*char *dst,*/ const char *src)
+{
+ unsigned len = strlen(src);
+ guarantee(len);
+ memcpy(dst, src, len);
+ dst += len;
+}
+
+/* HEADROOM bytes after dst are available after this call */
+static void fmt_url(/*char *dst,*/ const char *name)
+{
+ while (*name) {
+ unsigned c = *name++;
+ guarantee(3);
+ *dst = c;
+ if ((c - '0') > 9 /* not a digit */
+ && ((c|0x20) - 'a') > 26 /* not A-Z or a-z */
+ && !strchr("._-+@", c)
+ ) {
+ *dst++ = '%';
+ *dst++ = "0123456789ABCDEF"[c >> 4];
+ *dst = "0123456789ABCDEF"[c & 0xf];
+ }
+ dst++;
+ }
+}
+
+/* HEADROOM bytes are available after dst after this call */
+static void fmt_html(/*char *dst,*/ const char *name)
+{
+ while (*name) {
+ char c = *name++;
+ if (c == '<')
+ fmt_str("<");
+ else if (c == '>')
+ fmt_str(">");
+ else if (c == '&') {
+ fmt_str("&");
+ } else {
+ guarantee(1);
+ *dst++ = c;
+ continue;
+ }
+ }
+}
+
+/* HEADROOM bytes are available after dst after this call */
+static void fmt_ull(/*char *dst,*/ unsigned long long n)
+{
+ char buf[sizeof(n)*3 + 2];
+ char *p;
+
+ p = buf + sizeof(buf) - 1;
+ *p = '\0';
+ do {
+ *--p = (n % 10) + '0';
+ n /= 10;
+ } while (n);
+ fmt_str(/*dst,*/ p);
+}
+
+/* Does not call guarantee - eats into headroom instead */
+static void fmt_02u(/*char *dst,*/ unsigned n)
+{
+ /* n %= 100; - not needed, callers don't pass big n */
+ dst[0] = (n / 10) + '0';
+ dst[1] = (n % 10) + '0';
+ dst += 2;
+}
+
+/* Does not call guarantee - eats into headroom instead */
+static void fmt_04u(/*char *dst,*/ unsigned n)
+{
+ /* n %= 10000; - not needed, callers don't pass big n */
+ fmt_02u(n / 100);
+ fmt_02u(n % 100);
+}
+
int main(void)
{
dir_list_t *dir_list;
@@ -245,7 +240,6 @@
dirp = opendir(".");
if (!dirp)
return 1;
-
dir_list = NULL;
dir_list_count = 0;
while (1) {
@@ -266,66 +260,83 @@
dir_list[dir_list_count].dl_mtime = sb.st_mtime;
dir_list_count++;
}
+ closedir(dirp);
qsort(dir_list, dir_list_count, sizeof(dir_list[0]), (void*)compare_dl);
- /* Guard against directories wit &, > etc */
- QUERY_STRING = html_encode(QUERY_STRING);
- printf(str_header, QUERY_STRING, QUERY_STRING);
+ fmt_str(
+ "" /* Additional headers (currently none) */
+ "\r\n" /* Mandatory empty line after headers */
+ "<html><head><title>Index of ");
+ /* Guard against directories with &, > etc */
+ fmt_html(QUERY_STRING);
+ fmt_str(
+ "</title>\n"
+ STYLE_STR
+ "</head>" "\n"
+ "<body>" "\n"
+ "<h1>Index of ");
+ fmt_html(QUERY_STRING);
+ fmt_str(
+ "</h1>" "\n"
+ "<table>" "\n"
+ "<col class=nm><col class=sz><col class=dt>" "\n"
+ "<tr class=hdr><th class=cnt>Name<th class=sz>Size<th class=dt>Last modified" "\n");
odd = 0;
count_dirs = 0;
count_files = 0;
size_total = 0;
-
cdir = dir_list;
while (dir_list_count--) {
- char size_str[sizeof(long long) * 3];
- const char *slash_if_dir;
struct tm *tm;
- char *href;
- char *filename;
- char datetime_str[sizeof("2000-02-02 02:02:02")];
- slash_if_dir = "/";
if (S_ISDIR(cdir->dl_mode)) {
count_dirs++;
- size_str[0] = '\0';
} else if (S_ISREG(cdir->dl_mode)) {
count_files++;
size_total += cdir->dl_size;
- slash_if_dir++; /* points to "" now */
- sprintf(size_str, "%llu", (unsigned long long)(cdir->dl_size));
} else
goto next;
- href = url_encode(cdir->dl_name); /* %20 etc */
- filename = html_encode(cdir->dl_name); /* < etc */
+
+ fmt_str("<tr class=");
+ *dst++ = (odd ? 'o' : 'e');
+ fmt_str("><td class=nm><a href='");
+ fmt_url(cdir->dl_name); /* %20 etc */
+ if (S_ISDIR(cdir->dl_mode))
+ *dst++ = '/';
+ fmt_str("'>");
+ fmt_html(cdir->dl_name); /* < etc */
+ if (S_ISDIR(cdir->dl_mode))
+ *dst++ = '/';
+ fmt_str("</a><td class=sz>");
+ if (S_ISREG(cdir->dl_mode))
+ fmt_ull(cdir->dl_size);
+ fmt_str("<td class=dt>");
tm = gmtime(&cdir->dl_mtime);
- sprintf(datetime_str, "%04u-%02u-%02u %02u:%02u:%02u",
- (unsigned)(1900 + tm->tm_year),
- (unsigned)(tm->tm_mon + 1),
- (unsigned)(tm->tm_mday),
- (unsigned)(tm->tm_hour),
- (unsigned)(tm->tm_min),
- (unsigned)(tm->tm_sec)
- );
- printf("<tr class=%c><td class=nm><a href='%s%s'>%s%s</a><td class=sz>%s<td class=dt>%s\n",
- odd ? 'o' : 'e',
- href, slash_if_dir,
- filename, slash_if_dir,
- size_str,
- datetime_str
- );
- if (cdir->dl_name != href)
- free(href);
- if (cdir->dl_name != filename)
- free(filename);
+ fmt_04u(1900 + tm->tm_year); *dst++ = '-';
+ fmt_02u(tm->tm_mon + 1); *dst++ = '-';
+ fmt_02u(tm->tm_mday); *dst++ = ' ';
+ fmt_02u(tm->tm_hour); *dst++ = ':';
+ fmt_02u(tm->tm_min); *dst++ = ':';
+ fmt_02u(tm->tm_sec);
+ *dst++ = '\n';
+
odd = 1 - odd;
next:
cdir++;
}
+ fmt_str("<tr class=foot><th class=cnt>Files: ");
+ fmt_ull(count_files);
/* count_dirs - 1: we don't want to count ".." */
- printf(str_footer, count_files, count_dirs - 1, size_total);
+ fmt_str(", directories: ");
+ fmt_ull(count_dirs - 1);
+ fmt_str("<th class=sz>");
+ fmt_ull(size_total);
+ fmt_str("<th class=dt>\n");
+ /* "</table></body></html>" - why bother? */
+ guarantee(BUFFER_SIZE * 2); /* flush */
+
return 0;
}