12 static int intern_printf(int out, char *buf, size_t sz, const char *fmt, va_list ap);
13 static void bwrite(int out, char *buf, size_t buf_sz, char *str, int sz);
21 int puts(const char *s)
30 /* -- printf and friends -- */
32 int printf(const char *fmt, ...)
38 res = intern_printf(OUT_DEF, 0, 0, fmt, ap);
43 int vprintf(const char *fmt, va_list ap)
45 return intern_printf(OUT_DEF, 0, 0, fmt, ap);
48 int sprintf(char *buf, const char *fmt, ...)
54 res = intern_printf(OUT_BUF, buf, 0, fmt, ap);
59 int vsprintf(char *buf, const char *fmt, va_list ap)
61 return intern_printf(OUT_BUF, buf, 0, fmt, ap);
64 int snprintf(char *buf, size_t sz, const char *fmt, ...)
70 res = intern_printf(OUT_BUF, buf, sz, fmt, ap);
75 int vsnprintf(char *buf, size_t sz, const char *fmt, va_list ap)
77 return intern_printf(OUT_BUF, buf, sz, fmt, ap);
80 /* intern_printf provides all the functionality needed by all the printf
82 * - buf: optional buffer onto which the formatted results are written. If null
83 * then the output goes to the terminal through putchar calls. This is used
84 * by the (v)sprintf variants which write to an array of char.
85 * - sz: optional maximum size of the output, 0 means unlimited. This is used
86 * by the (v)snprintf variants to avoid buffer overflows.
87 * The rest are obvious, format string and variable argument list.
89 static char *convc = "dioxXucsfeEgGpn%";
91 #define IS_CONV(c) strchr(convc, c)
93 #define BUF(x) ((x) ? (x) + cnum : (x))
94 #define SZ(x) ((x) ? (x) - cnum : (x))
96 static int intern_printf(int out, char *buf, size_t sz, const char *fmt, va_list ap)
101 const char *fstart = 0;
132 bwrite(out, BUF(buf), SZ(sz), "0x", 2);
144 bwrite(out, BUF(buf), SZ(sz), "0", 1);
152 unum = va_arg(ap, unsigned int);
153 utoa(unum, conv_buf, base);
155 num = va_arg(ap, int);
156 itoa(num, conv_buf, base);
159 for(i=0; conv_buf[i]; i++) {
160 conv_buf[i] = toupper(conv_buf[i]);
164 slen = strlen(conv_buf);
167 if(!unsig && sign && num >= 0) {
168 bwrite(out, BUF(buf), SZ(sz), "+", 1);
171 bwrite(out, BUF(buf), SZ(sz), conv_buf, slen);
175 for(i=slen; i<fwidth; i++) {
176 bwrite(out, BUF(buf), SZ(sz), (char*)&padc, 1);
180 if(!unsig && sign && num >= 0) {
181 bwrite(out, BUF(buf), SZ(sz), "+", 1);
184 bwrite(out, BUF(buf), SZ(sz), conv_buf, slen);
191 char c = va_arg(ap, int);
192 bwrite(out, BUF(buf), SZ(sz), &c, 1);
198 str = va_arg(ap, char*);
202 bwrite(out, BUF(buf), SZ(sz), str, slen);
206 for(i=slen; i<fwidth; i++) {
207 bwrite(out, BUF(buf), SZ(sz), (char*)&padc, 1);
211 bwrite(out, BUF(buf), SZ(sz), str, slen);
217 *va_arg(ap, int*) = cnum;
224 /* restore default conversion state */
257 const char *fw = fmt;
258 while(*fmt && isdigit(*fmt)) fmt++;
267 bwrite(out, BUF(buf), SZ(sz), (char*)fmt++, 1);
276 /* bwrite is called by intern_printf to transparently handle writing into a
277 * buffer or to the terminal
279 static void bwrite(int out, char *buf, size_t buf_sz, char *str, int sz)
284 if(buf_sz && buf_sz <= sz) sz = buf_sz;
286 memcpy(buf, str, sz);
290 for(i=0; i<sz; i++) {