Leptonica 1.54
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SARRAY* getFilenamesInDirectory | ( | const char * | dirname | ) |
Input: directory name Return: sarray of file names, or NULL on error
Notes: (1) The versions compiled under unix and cygwin use the POSIX C library commands for handling directories. For windows, there is a separate implementation. (2) It returns an array of filename tails; i.e., only the part of the path after the last slash. (3) Use of the d_type field of dirent is not portable: "According to POSIX, the dirent structure contains a field char d_name[] of unspecified size, with at most NAME_MAX characters preceding the terminating null character. Use of other fields will harm the portability of your programs." (4) As a consequence of (3), we note several things:
SARRAY* getNumberedPathnamesInDirectory | ( | const char * | dirname, |
const char * | substr, | ||
l_int32 | numpre, | ||
l_int32 | numpost, | ||
l_int32 | maxnum | ||
) |
getNumberedPathnamesInDirectory()
Input: directory name substr (<optional> substring filter on filenames; can be NULL) numpre (number of characters in name before number) numpost (number of characters in name after number, up to a dot before an extension) including an extension and the dot separator) maxnum (only consider page numbers up to this value) Return: sarray of sorted pathnames, or NULL on error
Notes: (1) Returns the full pathnames of the numbered filenames in the directory. The number in the filename is the index into the sarray. For indices for which there are no filenames, an empty string ("") is placed into the sarray. This makes reading numbered files very simple. For example, the image whose filename includes number N can be retrieved using pixReadIndexed(sa, N); (2) If is not NULL, only filenames that contain the substring can be included. If is NULL, all matching filenames are used. (3) If no numbered files are found, it returns an empty sarray, with no initialized strings. (4) It is assumed that the page number is contained within the basename (the filename without directory or extension). is the number of characters in the basename preceeding the actual page number; is the number following the page number, up to either the end of the basename or a ".", whichever comes first. (5) To use a O(n) matching algorithm, the largest page number is found and two internal arrays of this size are created. This maximum is constrained not to exceed , to make sure that an unrealistically large number is not accidentally used to determine the array sizes.
SARRAY* getSortedPathnamesInDirectory | ( | const char * | dirname, |
const char * | substr, | ||
l_int32 | firstpage, | ||
l_int32 | npages | ||
) |
getSortedPathnamesInDirectory()
Input: directory name substr (<optional> substring filter on filenames; can be NULL) firstpage (0-based) npages (use 0 for all to the end) Return: sarray of sorted pathnames, or NULL on error
Notes: (1) If is not NULL, only filenames that contain the substring can be returned. If == NULL, none of the filenames are filtered out. (2) The files in the directory, after optional filtering by the substring, are lexically sorted in increasing order. The full pathnames are returned for the requested sequence. If no files are found after filtering, returns an empty sarray.
Input: sarray string (string to be added) copyflag (L_INSERT, L_COPY) Return: 0 if OK, 1 on error
Notes: (1) Legacy usage decrees that we always use 0 to insert a string directly and 1 to insert a copy of the string. The enums for L_INSERT and L_COPY agree with this convention, and will not change in the future. (2) See usage comments at the top of this file.
Input: filename sarray Return: 0 if OK; 1 on error
Input: sa1 (to be added to) sa2 (append specified range of strings in sa2 to sa1) start (index of first string of sa2 to append) end (index of last string of sa2 to append) Return: 0 if OK, 1 on error
Notes: (1) Copies of the strings in sarray2 are added to sarray1. (2) The [start ... end] range is truncated if necessary.
sarrayChangeRefCount()
Input: sarray delta (change to be applied) Return: 0 if OK, 1 on error
Input: sarray Return: 0 if OK; 1 on error
Input: sarray Return: ptr to same sarray, or null on error
Input: sa1 (to be added to) sa2 (append to sa1) Return: 0 if OK, 1 on error
Notes: (1) Copies of the strings in sarray2 are added to sarray1.
Input: sa (sa of individual words) linesize (max num of chars in each line) Return: saout (sa of formatted lines), or null on error
This is useful for re-typesetting text to a specific maximum line length. The individual words in the input sarray are concatenated into textlines. An input word string of zero length is taken to be a paragraph separator. Each time such a string is found, the current line is ended and a new line is also produced that contains just the string of zero length (""). When the output sarray of lines is eventually converted to a string with newlines (typically) appended to each line string, the empty strings are just converted to newlines, producing the visible paragraph separation.
What happens when a word is larger than linesize? We write it out as a single line anyway! Words preceding or following this long word are placed on lines preceding or following the line with the long word. Why this choice? Long "words" found in text documents are typically URLs, and it's often desirable not to put newlines in the middle of a URL. The text display program (e.g., text editor) will typically wrap the long "word" to fit in the window.
Input: sarray Return: copy of sarray, or null on error
Input: size of string ptr array to be alloc'd (use 0 for default) Return: sarray, or null on error
Input: n (size of string ptr array to be alloc'd) initstr (string to be initialized on the full array) Return: sarray, or null on error
Input: string blankflag (0 to exclude blank lines; 1 to include) Return: sarray, or null on error
Notes: (1) This finds the number of line substrings, each of which ends with a newline, and puts a copy of each substring in a new sarray. (2) The newline characters are removed from each substring.
SARRAY* sarrayCreateWordsFromString | ( | const char * | string | ) |
Input: string Return: sarray, or null on error
Notes: (1) This finds the number of word substrings, creates an sarray of this size, and puts copies of each substring into the sarray.
void sarrayDestroy | ( | SARRAY ** | psa | ) |
Input: &sarray <to be="" nulled>=""> Return: void
Notes: (1) Decrements the ref count and, if 0, destroys the sarray. (2) Always nulls the input ptr.
Input: sarray Return: 0 if OK, 1 on error
Input: sarray &nalloc (<optional return>=""> number allocated string ptrs) &n (<optional return>=""> number allocated strings) Return: ptr to string array, or null on error
Notes: (1) Caution: the returned array is not a copy, so caller must not destroy it!
Input: sarray Return: count, or 0 if no strings or on error
sarrayGetRefCount()
Input: sarray Return: refcount, or UNDEF on error
Input: sarray index (to the index-th string) copyflag (L_NOCOPY or L_COPY) Return: string, or null on error
Notes: (1) Legacy usage decrees that we always use 0 to get the pointer to the string itself, and 1 to get a copy of the string. (2) See usage comments at the top of this file. (3) To get a pointer to the string itself, use for copyflag: L_NOCOPY or 0 or FALSE To get a copy of the string, use for copyflag: L_COPY or 1 or TRUE The const values of L_NOCOPY and L_COPY are guaranteed not to change.
Input: sa1, sa2 padstring Return: 0 if OK, 1 on error
Notes: (1) If two sarrays have different size, this adds enough instances of to the smaller so that they are the same size. It is useful when two or more sarrays are being sequenced in parallel, and it is necessary to find a valid string at each index.
l_int32 sarrayParseRange | ( | SARRAY * | sa, |
l_int32 | start, | ||
l_int32 * | pactualstart, | ||
l_int32 * | pend, | ||
l_int32 * | pnewstart, | ||
const char * | substr, | ||
l_int32 | loc | ||
) |
Input: sa (input sarray) start (index to start range search) &actualstart (<return> index of actual start; may be > 'start') &end (<return> index of end) &newstart (<return> index of start of next range) substr (substring for matching at beginning of string) loc (byte offset within the string for the pattern; use -1 if the location does not matter); Return: 0 if valid range found; 1 otherwise
Notes: (1) This finds the range of the next set of strings in SA, beginning the search at 'start', that does NOT have the substring 'substr' either at the indicated location in the string or anywhere in the string. The input variable 'loc' is the specified offset within the string; use -1 to indicate 'anywhere in the string'. (2) Always check the return value to verify that a valid range was found. (3) If a valid range is not found, the values of actstart, end and newstart are all set to the size of sa. (4) If this is the last valid range, newstart returns the value n. In use, this should be tested before calling the function. (5) Usage example. To find all the valid ranges in a file where the invalid lines begin with two dashes, copy each line in the file to a string in an sarray, and do: start = 0; while (!sarrayParseRange(sa, start, &actstart, &end, &start, "--", 0)) fprintf(stderr, "start = %d, end = %d\n", actstart, end);
SARRAY* sarrayRead | ( | const char * | filename | ) |
Input: filename Return: sarray, or null on error
SARRAY* sarrayReadStream | ( | FILE * | fp | ) |
Input: stream Return: sarray, or null on error
Notes: (1) We store the size of each string along with the string. (2) This allows a string to have embedded newlines. By reading the entire string, as determined by its size, we are not affected by any number of embedded newlines.
Input: sarray index (of string within sarray) Return: removed string, or null on error
Input: sarray index (of string within sarray to be replaced) newstr (string to replace existing one) copyflag (L_INSERT, L_COPY) Return: 0 if OK, 1 on error
Notes: (1) This destroys an existing string and replaces it with the new string or a copy of it. (2) By design, an sarray is always compacted, so there are never any holes (null ptrs) in the ptr array up to the current count.
Input: sain (input sarray) first (index of first string to be selected) last (index of last string to be selected; use 0 to go to the end of the sarray) Return: saout (output sarray), or null on error
Notes: (1) This makes consisting of copies of all strings in in the index set [first ... last]. Use == 0 to get all strings from to the last string in the sarray.
Input: sain (input sarray) substr (<optional> substring for matching; can be NULL) Return: saout (output sarray, filtered with substring) or null on error
Notes: (1) This selects all strings in sain that have substr as a substring. Note that we can't use strncmp() because we're looking for a match to the substring anywhere within each filename. (2) If substr == NULL, returns a copy of the sarray.
Input: saout (output sarray; can be NULL or equal to sain) sain (input sarray) sortorder (L_SORT_INCREASING or L_SORT_DECREASING) Return: saout (output sarray, sorted by ascii value), or null on error
Notes: (1) Set saout = sain for in-place; otherwise, set naout = NULL. (2) Shell sort, modified from K&R, 2nd edition, p.62. Slow but simple O(n logn) sort.
Input: sarray addnlflag (flag: 0 adds nothing to each substring 1 adds '
' to each substring 2 adds ' ' to each substring) Return: dest string, or null on error
Notes: (1) Concatenates all the strings in the sarray, preserving all white space. (2) If addnlflag != 0, adds either a '
' or a ' ' after each substring. (3) This function was NOT implemented as: for (i = 0; i < n; i++) strcat(dest, sarrayGetString(sa, i, L_NOCOPY)); Do you see why?
Input: sarray first (index of first string to use; starts with 0) nstrings (number of strings to append into the result; use 0 to append to the end of the sarray) addnlflag (flag: 0 adds nothing to each substring 1 adds '
' to each substring 2 adds ' ' to each substring) Return: dest string, or null on error
Notes: (1) Concatenates the specified strings inthe sarray, preserving all white space. (2) If addnlflag != 0, adds either a '
' or a ' ' after each substring. (3) If the sarray is empty, this returns a string with just the character corresponding to .
Input: filename sarray Return: 0 if OK; 1 on error
Input: stream sarray Returns 0 if OK; 1 on error
Notes: (1) This appends a '
' to each string, which is stripped off by sarrayReadStream().
l_int32 stringCompareLexical | ( | const char * | str1, |
const char * | str2 | ||
) |
Input: str1 str2 Return: 1 if str1 > str2 (lexically); 0 otherwise
Notes: (1) If the lexical values are identical, return a 0, to indicate that no swapping is required to sort the strings.
const l_int32 INITIAL_PTR_ARRAYSIZE = 50 [static] |
const l_int32 L_BUF_SIZE = 512 [static] |