ps: fix overflow in USER and VSZ columns

[oweals/busybox.git] / libbb / xfuncs.c

diff --git a/libbb/xfuncs.c b/libbb/xfuncs.c
index 6d8eac4b6b72cf1b003c9ce69095e679dcf16412..6d50bf9bc71ca6bec082ebbfbd63540470dc089a 100644 (file)
--- a/libbb/xfuncs.c
+++ b/libbb/xfuncs.c
@@ -282,10 +282,10 @@ void xsetenv(const char *key, const char *value)
                bb_error_msg_and_die(bb_msg_memory_exhausted);
 }
 
-// Converts unsigned long long value into compact 4-char
-// representation. Examples: "1234", "1.2k", " 27M", "123T"
-// Fifth char is always '\0'
-void smart_ulltoa5(unsigned long long ul, char buf[5])
+/* Converts unsigned long long value into compact 4-char
+ * representation. Examples: "1234", "1.2k", " 27M", "123T"
+ * String is not terminated (buf[4] is untouched) */
+void smart_ulltoa4(unsigned long long ul, char buf[5], const char *scale)
 {
        const char *fmt;
        char c;
@@ -327,13 +327,66 @@ void smart_ulltoa5(unsigned long long ul, char buf[5])
                        buf[1] = '.';
                }
                buf[2] = "0123456789"[v];
-               // see http://en.wikipedia.org/wiki/Tera
-               // (small letters stand out better versus numbers)
-               buf[3] = " kmgtpezy"[idx];
+               buf[3] = scale[idx]; /* typically scale = " kmgt..." */
        }
-       buf[4] = '\0';
 }
 
+/* Converts unsigned long long value into compact 5-char representation.
+ * String is not terminated (buf[5] is untouched) */
+void smart_ulltoa5(unsigned long long ul, char buf[6], const char *scale)
+{
+       const char *fmt;
+       char c;
+       unsigned v, u, idx = 0;
+
+       if (ul > 99999) { // do not scale if 99999 or less
+               ul *= 10;
+               do {
+                       ul /= 1024;
+                       idx++;
+               } while (ul >= 100000);
+       }
+       v = ul; // ullong divisions are expensive, avoid them
+
+       fmt = " 123456789";
+       u = v / 10;
+       v = v % 10;
+       if (!idx) {
+               // 99999 or less: use "12345" format
+               // u is value/10, v is last digit
+               c = buf[0] = " 123456789"[u/1000];
+               if (c != ' ') fmt = "0123456789";
+               c = buf[1] = fmt[u/100%10];
+               if (c != ' ') fmt = "0123456789";
+               c = buf[2] = fmt[u/10%10];
+               if (c != ' ') fmt = "0123456789";
+               buf[3] = fmt[u%10];
+               buf[4] = "0123456789"[v];
+       } else {
+               // value has been scaled into 0..9999.9 range
+               // u is value, v is 1/10ths (allows for 92.1M format)
+               if (u >= 100) {
+                       // value is >= 100: use "1234M', " 123M" formats
+                       c = buf[0] = " 123456789"[u/1000];
+                       if (c != ' ') fmt = "0123456789";
+                       c = buf[1] = fmt[u/100%10];
+                       if (c != ' ') fmt = "0123456789";
+                       v = u % 10;
+                       u = u / 10;
+                       buf[2] = fmt[u%10];
+               } else {
+                       // value is < 100: use "92.1M" format
+                       c = buf[0] = " 123456789"[u/10];
+                       if (c != ' ') fmt = "0123456789";
+                       buf[1] = fmt[u%10];
+                       buf[2] = '.';
+               }
+               buf[3] = "0123456789"[v];
+               buf[4] = scale[idx]; /* typically scale = " kmgt..." */
+       }
+}
+
+
 // Convert unsigned integer to ascii, writing into supplied buffer.
 // A truncated result contains the first few digits of the result ala strncpy.
 // Returns a pointer past last generated digit, does _not_ store NUL.