diff options
Diffstat (limited to 'src/scrotty.c')
-rw-r--r-- | src/scrotty.c | 152 |
1 files changed, 138 insertions, 14 deletions
diff --git a/src/scrotty.c b/src/scrotty.c index ecfa072..286a30d 100644 --- a/src/scrotty.c +++ b/src/scrotty.c @@ -33,7 +33,9 @@ #include <string.h> #include <stdlib.h> #include <stdint.h> +#include <stdio.h> #include <alloca.h> +#include <time.h> #ifndef PATH_MAX @@ -259,12 +261,128 @@ static int measure(int fbno, long* width, long* height) /** + * Duplicate all '%':s in a buffer until the first occurrence of a zero byte + * + * @param buf The buffer + * @param n The size of the buffer + * @return -1 if the buffer is too small, otherwise + * the new position of the first zero byte + */ +static ssize_t duplicate_percents(char* restrict buf, size_t n) +{ + size_t p = 0, pi, pc = 0, i; + + /* Count number of '%':s. */ + for (i = 0; buf[i]; i++) + if (buf[i] == '%') + pc++; + + /* Check whether the string will overflow. */ + if (i + pc > n) + return -1; + + /* Duplicate all '%':s. */ + for (pi = 0; pi < pc; pi++) + { + p = (size_t)(strchr(buf + p, '%') - buf); + memmove(buf + p + 1, buf + p, (i - (p - pi)) * sizeof(char)); + p += 2; + } + + return (ssize_t)(i + pi); +} + + +/** + * Parse and evaluate a --exec argument or filename pattern + * + * If `path != NULL` than all non-escaped spaces in + * `pattern` will be stored as 255-bytes in `buf`. + * + * @param buf The output buffer + * @param n The size of `buf` + * @param pattern The pattern to evaluate + * @param fbno The index of the framebuffer + * @param width The width of the image/framebuffer + * @param height The height of the image/framebuffer + * @param path The filename of the saved image, `NULL` during the evaluation of the filename pattern + * @return Zero on success, -1 on error + */ +static int evaluate(char* restrict buf, size_t n, const char* restrict pattern, + int fbno, long width, long height, const char* restrict path) +{ +#define p(format, value) r = snprintf(buf + i, n - i, format "%zn", value, &j) + + size_t i = 0; + ssize_t j = 0; + int percent = 0, backslash = 0, dollar = 0, r; + char c; + char* fmt; + time_t t; + struct tm tm; + + while ((c = *pattern++)) + { + if (dollar) + { + dollar = 0; + if (path == NULL) + if ((c == 'f') || (c == 'n')) + continue; + if (c == 'i') p("%i", fbno); + else if (c == 'f') p("%s", path); + else if (c == 'n') p("%s", strrchr(path, '/') ? (strrchr(path, '/') + 1) : path); + else if (c == 'p') p("%ju", (uintmax_t)width * (uintmax_t)height); + else if (c == 'w') p("%li", width); + else if (c == 'h') p("%li", height); + else if (c == '$') r = 0, j = 1, buf[i] = '$'; + else + continue; + if ((r < 0) || (j <= 0)) + return -1; + if ((c == 'f') || (c == 'n')) + if (j = duplicate_percents(buf + i, n - i), j < 0) + return errno = ENAMETOOLONG, -1; + i += (size_t)j; + } + else if (backslash) buf[i++] = (c == 'n' ? '\n' : c), backslash = 0; + else if (percent) buf[i++] = c, percent = 0; + else if (c == '%') buf[i++] = c, percent = 1; + else if (c == '\\') backslash = 1; + else if (c == '$') dollar = 1; + else if (c == ' ') buf[i++] = path == NULL ? ' ' : 255; /* 255 is not valid in UTF-8. */ + else buf[i++] = c; + + if (i >= n) + return errno = ENAMETOOLONG, -1; + } + buf[i] = '\0'; + + if (strchr(buf, '%') == NULL) + return 0; + + fmt = alloca((strlen(buf) + 1) * sizeof(char)); + memcpy(fmt, buf, (strlen(buf) + 1) * sizeof(char)); + + t = time(NULL); + localtime_r(&t, &tm); + if (strftime(buf, n, fmt, &tm) == 0) + return errno = ENAMETOOLONG, -1; + + return 0; + +#undef p +} + + +/** * Take a screenshot of a framebuffer * - * @param fbno The number of the framebuffer - * @return Zero on success, -1 on error, 1 if the framebuffer does not exist + * @param fbno The number of the framebuffer + * @param filepattern The pattern for the filename, `NULL` for default + * @return Zero on success, -1 on error, 1 if the framebuffer does not exist */ -static int save_fb(int fbno) +static int save_fb(int fbno, const char* filepattern) { char fbpath[PATH_MAX]; char imgpath[PATH_MAX]; @@ -279,16 +397,22 @@ static int save_fb(int fbno) /* Get the size of the framebuffer. */ if (measure(fbno, &width, &height) < 0) return -1; - + /* Get output pathname. */ - sprintf(imgpath, "fb%i.png", fbno); - if (access(imgpath, F_OK) == 0) - for (i = 2;; i++) - { - sprintf(imgpath, "fb%i.png.%i", fbno, i); - if (access(imgpath, F_OK)) - break; - } + if (filepattern == NULL) + { + sprintf(imgpath, "fb%i.png", fbno); + if (access(imgpath, F_OK) == 0) + for (i = 2;; i++) + { + sprintf(imgpath, "fb%i.png.%i", fbno, i); + if (access(imgpath, F_OK)) + break; + } + } + else + if (evaluate(imgpath, PATH_MAX, filepattern, fbno, width, height, NULL) < 0) + return -1; /* Take a screenshot of the current framebuffer. */ if (save(fbpath, imgpath, fbno, width, height) < 0) @@ -415,7 +539,7 @@ int main(int argc, char* argv[]) else if ((argv[i][0] == '-') || (filepattern != -1)) return fprintf(stderr, "Unrecognised option. Type `%s --help` for help.\n", execname), 1; else - filepattern = i; /* TODO use this */ + filepattern = i; } /* Check that --exec is valid. */ @@ -439,7 +563,7 @@ int main(int argc, char* argv[]) /* Take a screenshot of each framebuffer. */ for (fbno = 0;; fbno++) { - r = save_fb(fbno); + r = save_fb(fbno, filepattern < 0 ? NULL : argv[filepattern]); if (r < 0) return perror(execname), 1; if (r > 0) break; } |