| Message ID | 1386932286-10723-2-git-send-email-drjones@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Fri, Dec 13, 2013 at 11:58:04AM +0100, Andrew Jones wrote: > Support format flags for field padding, such as "%08x", allowing > register dumps to be easier on the eyes. > > Signed-off-by: Andrew Jones <drjones@redhat.com> > --- > lib/printf.c | 84 ++++++++++++++++++++++++++++++++++++++++++++++++++---------- > 1 file changed, 70 insertions(+), 14 deletions(-) > > diff --git a/lib/printf.c b/lib/printf.c > index 867eb1926f742..dd20f755c01a0 100644 > --- a/lib/printf.c > +++ b/lib/printf.c > @@ -6,6 +6,11 @@ typedef struct pstream { > int added; > } pstream_t; > > +typedef struct strprops { > + char pad; > + int npad; > +} strprops_t; > + > static void addchar(pstream_t *p, char c) > { > if (p->remain) { > @@ -15,15 +20,37 @@ static void addchar(pstream_t *p, char c) > ++p->added; > } > > -void print_str(pstream_t *p, const char *s) > +void print_str(pstream_t *p, const char *s, strprops_t props) > { > + const char *s_orig = s; > + int npad = props.npad; > + > + if (npad > 0) { > + npad -= strlen(s_orig); > + while (npad > 0) { > + addchar(p, props.pad); > + --npad; > + } > + } > + > while (*s) > addchar(p, *s++); > + > + if (npad < 0) { > + char pad = props.pad; > + if (pad == '0') /* ignore '0' flag with '-' flag */ > + pad = ' '; there are only the two options, so you can drop the check if you like. > + npad += strlen(s_orig); > + while (npad < 0) { > + addchar(p, pad); > + ++npad; > + } > + } > } > > static char digits[16] = "0123456789abcdef"; > > -void print_int(pstream_t *ps, long long n, int base) > +void print_int(pstream_t *ps, long long n, int base, strprops_t props) > { > char buf[sizeof(long) * 3 + 2], *p = buf; > int s = 0, i; > @@ -54,10 +81,11 @@ void print_int(pstream_t *ps, long long n, int base) > > *p = 0; > > - print_str(ps, buf); > + print_str(ps, buf, props); > } > > -void print_unsigned(pstream_t *ps, unsigned long long n, int base) > +void print_unsigned(pstream_t *ps, unsigned long long n, int base, > + strprops_t props) > { > char buf[sizeof(long) * 3 + 1], *p = buf; > int i; > @@ -80,7 +108,23 @@ void print_unsigned(pstream_t *ps, unsigned long long n, int base) > > *p = 0; > > - print_str(ps, buf); > + print_str(ps, buf, props); > +} > + > +static int fmtnum(const char **fmt) > +{ > + const char *f = *fmt; > + int len = 0, num; > + > + if (*f == '-') > + ++f, ++len; oh wow, this deserves a small comment saying that negative values are used to add trailing padding instead of leading. > + > + while (*f >= '0' && *f <= '9') > + ++f, ++len; > + > + num = atol(*fmt); > + *fmt += len; > + return num; > } some funny indentation is back here... Better check your entire patch for that. > > int vsnprintf(char *buf, int size, const char *fmt, va_list va) > @@ -93,6 +137,9 @@ int vsnprintf(char *buf, int size, const char *fmt, va_list va) > while (*fmt) { > char f = *fmt++; > int nlong = 0; > + strprops_t props; > + memset(&props, 0, sizeof(props)); > + props.pad = ' '; > > if (f != '%') { > addchar(&s, f); > @@ -110,41 +157,50 @@ int vsnprintf(char *buf, int size, const char *fmt, va_list va) > case '\0': > --fmt; > break; > + case '0': > + props.pad = '0'; > + ++fmt; > + /* fall through */ > + case '1'...'9': > + case '-': > + --fmt; > + props.npad = fmtnum(&fmt); > + goto morefmt; > case 'l': > ++nlong; > goto morefmt; > case 'd': > switch (nlong) { > case 0: > - print_int(&s, va_arg(va, int), 10); > + print_int(&s, va_arg(va, int), 10, props); > break; > case 1: > - print_int(&s, va_arg(va, long), 10); > + print_int(&s, va_arg(va, long), 10, props); > break; > default: > - print_int(&s, va_arg(va, long long), 10); > + print_int(&s, va_arg(va, long long), 10, props); > break; > } > break; > case 'x': > switch (nlong) { > case 0: > - print_unsigned(&s, va_arg(va, unsigned), 16); > + print_unsigned(&s, va_arg(va, unsigned), 16, props); > break; > case 1: > - print_unsigned(&s, va_arg(va, unsigned long), 16); > + print_unsigned(&s, va_arg(va, unsigned long), 16, props); > break; > default: > - print_unsigned(&s, va_arg(va, unsigned long long), 16); > + print_unsigned(&s, va_arg(va, unsigned long long), 16, props); > break; > } > break; > case 'p': > - print_str(&s, "0x"); > - print_unsigned(&s, (unsigned long)va_arg(va, void *), 16); > + print_str(&s, "0x", props); > + print_unsigned(&s, (unsigned long)va_arg(va, void *), 16, props); > break; > case 's': > - print_str(&s, va_arg(va, const char *)); > + print_str(&s, va_arg(va, const char *), props); > break; > default: > addchar(&s, f); > -- > 1.8.1.4 > Besides the formatting stuff: Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Sat, Dec 28, 2013 at 10:31:44PM -0800, Christoffer Dall wrote: > > + > > + if (npad < 0) { > > + char pad = props.pad; > > + if (pad == '0') /* ignore '0' flag with '-' flag */ > > + pad = ' '; > > there are only the two options, so you can drop the check if > you like. true. removed. > > +static int fmtnum(const char **fmt) > > +{ > > + const char *f = *fmt; > > + int len = 0, num; > > + > > + if (*f == '-') > > + ++f, ++len; > > oh wow, this deserves a small comment saying that negative values are > used to add trailing padding instead of leading. You mean something beyond "man 3 printf; /flag"? :-) > > > + > > + while (*f >= '0' && *f <= '9') > > + ++f, ++len; > > + > > + num = atol(*fmt); > > + *fmt += len; > > + return num; > > } > > some funny indentation is back here... Better check your entire patch > for that. The whole file has the funny indentation, I just followed suit. The alternative is to add a patch that "fixes" all the pre-existing lib/* files first, but for this patch I didn't think it was worth it. drew -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Thu, Jan 02, 2014 at 06:09:48PM +0100, Andrew Jones wrote: > On Sat, Dec 28, 2013 at 10:31:44PM -0800, Christoffer Dall wrote: > > > + > > > + if (npad < 0) { > > > + char pad = props.pad; > > > + if (pad == '0') /* ignore '0' flag with '-' flag */ > > > + pad = ' '; > > > > there are only the two options, so you can drop the check if > > you like. > > true. removed. > > > > +static int fmtnum(const char **fmt) > > > +{ > > > + const char *f = *fmt; > > > + int len = 0, num; > > > + > > > + if (*f == '-') > > > + ++f, ++len; > > > > oh wow, this deserves a small comment saying that negative values are > > used to add trailing padding instead of leading. > > You mean something beyond "man 3 printf; /flag"? :-) > yes, that's a functional description, not helping the reader of the implememtation. But ok, once this works, it's not likely to pass many eyes again. > > > > > + > > > + while (*f >= '0' && *f <= '9') > > > + ++f, ++len; > > > + > > > + num = atol(*fmt); > > > + *fmt += len; > > > + return num; > > > } > > > > some funny indentation is back here... Better check your entire patch > > for that. > > The whole file has the funny indentation, I just followed suit. The > alternative is to add a patch that "fixes" all the pre-existing lib/* > files first, but for this patch I didn't think it was worth it. > fair enough, but it really hurts when reading patches so we should fix this some time... -Christoffer -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/lib/printf.c b/lib/printf.c index 867eb1926f742..dd20f755c01a0 100644 --- a/lib/printf.c +++ b/lib/printf.c @@ -6,6 +6,11 @@ typedef struct pstream { int added; } pstream_t; +typedef struct strprops { + char pad; + int npad; +} strprops_t; + static void addchar(pstream_t *p, char c) { if (p->remain) { @@ -15,15 +20,37 @@ static void addchar(pstream_t *p, char c) ++p->added; } -void print_str(pstream_t *p, const char *s) +void print_str(pstream_t *p, const char *s, strprops_t props) { + const char *s_orig = s; + int npad = props.npad; + + if (npad > 0) { + npad -= strlen(s_orig); + while (npad > 0) { + addchar(p, props.pad); + --npad; + } + } + while (*s) addchar(p, *s++); + + if (npad < 0) { + char pad = props.pad; + if (pad == '0') /* ignore '0' flag with '-' flag */ + pad = ' '; + npad += strlen(s_orig); + while (npad < 0) { + addchar(p, pad); + ++npad; + } + } } static char digits[16] = "0123456789abcdef"; -void print_int(pstream_t *ps, long long n, int base) +void print_int(pstream_t *ps, long long n, int base, strprops_t props) { char buf[sizeof(long) * 3 + 2], *p = buf; int s = 0, i; @@ -54,10 +81,11 @@ void print_int(pstream_t *ps, long long n, int base) *p = 0; - print_str(ps, buf); + print_str(ps, buf, props); } -void print_unsigned(pstream_t *ps, unsigned long long n, int base) +void print_unsigned(pstream_t *ps, unsigned long long n, int base, + strprops_t props) { char buf[sizeof(long) * 3 + 1], *p = buf; int i; @@ -80,7 +108,23 @@ void print_unsigned(pstream_t *ps, unsigned long long n, int base) *p = 0; - print_str(ps, buf); + print_str(ps, buf, props); +} + +static int fmtnum(const char **fmt) +{ + const char *f = *fmt; + int len = 0, num; + + if (*f == '-') + ++f, ++len; + + while (*f >= '0' && *f <= '9') + ++f, ++len; + + num = atol(*fmt); + *fmt += len; + return num; } int vsnprintf(char *buf, int size, const char *fmt, va_list va) @@ -93,6 +137,9 @@ int vsnprintf(char *buf, int size, const char *fmt, va_list va) while (*fmt) { char f = *fmt++; int nlong = 0; + strprops_t props; + memset(&props, 0, sizeof(props)); + props.pad = ' '; if (f != '%') { addchar(&s, f); @@ -110,41 +157,50 @@ int vsnprintf(char *buf, int size, const char *fmt, va_list va) case '\0': --fmt; break; + case '0': + props.pad = '0'; + ++fmt; + /* fall through */ + case '1'...'9': + case '-': + --fmt; + props.npad = fmtnum(&fmt); + goto morefmt; case 'l': ++nlong; goto morefmt; case 'd': switch (nlong) { case 0: - print_int(&s, va_arg(va, int), 10); + print_int(&s, va_arg(va, int), 10, props); break; case 1: - print_int(&s, va_arg(va, long), 10); + print_int(&s, va_arg(va, long), 10, props); break; default: - print_int(&s, va_arg(va, long long), 10); + print_int(&s, va_arg(va, long long), 10, props); break; } break; case 'x': switch (nlong) { case 0: - print_unsigned(&s, va_arg(va, unsigned), 16); + print_unsigned(&s, va_arg(va, unsigned), 16, props); break; case 1: - print_unsigned(&s, va_arg(va, unsigned long), 16); + print_unsigned(&s, va_arg(va, unsigned long), 16, props); break; default: - print_unsigned(&s, va_arg(va, unsigned long long), 16); + print_unsigned(&s, va_arg(va, unsigned long long), 16, props); break; } break; case 'p': - print_str(&s, "0x"); - print_unsigned(&s, (unsigned long)va_arg(va, void *), 16); + print_str(&s, "0x", props); + print_unsigned(&s, (unsigned long)va_arg(va, void *), 16, props); break; case 's': - print_str(&s, va_arg(va, const char *)); + print_str(&s, va_arg(va, const char *), props); break; default: addchar(&s, f);
Support format flags for field padding, such as "%08x", allowing register dumps to be easier on the eyes. Signed-off-by: Andrew Jones <drjones@redhat.com> --- lib/printf.c | 84 ++++++++++++++++++++++++++++++++++++++++++++++++++---------- 1 file changed, 70 insertions(+), 14 deletions(-)